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Re: 1962 Catalina [Re: Magnetoman] #674568 11/15/16 7:54 pm
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That's one handsome machine. Makes mine look like a pile of rust..
I love the sound of a straight thru' pipe & it looks better I think but not sure my ears would say the same after a long ride, let alone what the traffic officers might say!
Great info too on the LED set-up on the other thread, thanks for that, it saves others a lot of time going over the same research.
Re. the Catalina tank, were they ever supplied in metallic red for the GS or was that only on the twins?
I've seen 2 types of these 2 gallon tanks, some with fuel taps in the usual position close to the seat end & others with taps a long way forward, nearer the centre of the tank. I assume once again that is a singles / twins variation.



na
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Re: 1962 Catalina [Re: flowboy] #674582 11/15/16 10:26 pm
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Originally Posted by flowboy
Re. the Catalina tank, were they ever supplied in metallic red for the GS or was that only on the twins
As far as I'm aware the sales brochures only showed the Catalina tank in blue.

Re: 1962 Catalina [Re: Magnetoman] #674682 11/16/16 7:48 pm
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Thought that was most likely, I've only ever seen blue tanks on the few Cat's I've seen.
Had a feeling I'd seen a list of export colours other than blue but can't recall where.
My '58 500 came with a 2 gall tank in a metallic / flamboyant red with gold lining. Definitely the original paint but the tank could easily have come from a twin.


na
Re: 1962 Catalina [Re: Magnetoman] #674695 11/16/16 9:40 pm
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Early (56-58) Catalina Scramblers were silver. 59-62 Catalina's Sapphire Blue. 63 Eastern Black.
63 Western brochure refers to "rich enamels", mostly Sapphire blue but I have seen a few in red.


Coming to terms with your delusions, is the first step to sanity
Re: 1962 Catalina [Re: Magnetoman] #677318 12/11/16 5:14 pm
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A few months ago I sent Michael Morse of Vintage Brake an 8" front brake backing plate to have new shoes installed and arced to the diameter I measured of the drum. I actually sent him the backing plate from my Special Competition since it was sitting in a box thanks to the Eddie Dow TLS I have on it. Anyway, Michael always has a backlog but two weeks ago he called to say he was about to arc the shoes when he discovered one of the pivots was slightly crooked, at which point he discovered the plate was cracked. That evening I removed the backing plate from the Catalina to ship to him, which wasn't a trivial task since the bike is on a lift due to my work on its 6-spring clutch.

The good news is he called last week to say it was done. The bad news is earlier this week UPS tracking showed the box was dropped off at my house. Except, it wasn't. Unfortunately for me is I had told Michael to insure it for the $100 minimum so if it doesn't turn up I will be out ~$150 and still not have the brake.

The only way to increase the odds of the package being located is if I wasted a lot of my time installing yet another brake on the Catalina. I mean, if I just crossed my fingers and hoped UPS would find it, they wouldn't. Only by wasting lots of time doing work that would prove unnecessary if the package later turned up would there be any hope. So, yesterday went about doing that.

Making an all-day story short, after finding an appropriate backing plate amongst the wheels on a rack ~10' off the floor, polishing the worst of the oxidation off it, fighting the springs to remove worn shoes and replace them with the best set I could find, finding an actuating arm on another backing plate on that rack and painting it, etc., I installed it on the Catalina. Just replacing the wheel in the forks itself also takes time.

I finally reached the step of hooking up the brake cable only to discover that I hadn't noticed the backing plate did not have the necessary mounting point for the cable, only a plain end fastener at that location as shown in the bottom of the photograph.

[Linked Image]

Searching for the necessary component (which is also one of the pivots for the shoes) I found one on the backing plate for my M21. Unfortunately, it was at the very bottom of a pile of six wheels on the top shelf of an 8' shelving unit. Wheels double their weight when precariously stacked 8' off the ground so it took some effort to unearth it from the pile.

Leaving out the ugly details, an hour later I had the component installed in the backing plate, and the wheel back on the Catalina.

[Linked Image]

The bike is still not quite ready to ride since in the next few days a package with a Trident clutch cable will be delivered. Since it will be easier to install that cable (after modifying it) with the bike on the lift, I'll postpone for another week taking the bike off the lift and moving bikes around so I can get it out of the garage.

Sometimes progress isn't just slow, it's expensive as well as frustrating. Three months ago the Catalina had a front brake that was OK, not great. Three months, several hundred dollars, and at least eight working hours later the front brake is back to where it was on September 19 when I shipped the first backing plate to Vintage Brake (note: in case it isn't clear, none of this misadventure is the fault of Vintage Brake).


Update: actually, it was the fault of Vintage Brake. Michael hadn't updated his records and so he shipped it to my old address. Our real estate agent called my wife this afternoon to say a package had been delivered to our old house and they had given it to her and it was now being held at the real estate company's office. Conveniently, the office was on the route I take home.

Assuming there are any logical, analytical experimental scientists who aren't superstitious, note that yesterday I wrote "Only by wasting lots of time doing work that would prove unnecessary if the package later turned up would there be any hope." Twelve hours after writing those words the package is in my hands. I ask you, how can someone not be superstitious?...

Last edited by Magnetoman; 12/12/16 7:25 pm. Reason: Update:
Re: 1962 Catalina [Re: Magnetoman] #677404 12/12/16 11:00 am
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I notice that you do just as I do for old Brit brakes- Trident clutch cable and aftermarket "wedge" fitting)I think they were Webco, I know Emgo sells them now). I cut the cable as short and direct as I can and still have room for the suspension. I have found it to make the biggest single change in braking power. I have the set up on my '67 Velo Venom. Years ago I met up with an acquaintance with a Thruxton that had just been restored by a high end shop. My Venom had the SLS brake. The Thruxton had a DLS. Before he took my bike for a spin, he was raving about the brake on his Thruxton. He came back and wanted to know what I had done, because my brake was better. The Velo gets such a noticeable result because the stock cable is pretty wimpy and way too long with a big loop in it. I also find this mod helpful on conical hubs with the cable brake light switch.

Ed from NJ

Re: 1962 Catalina [Re: edunham] #677477 12/12/16 4:52 pm
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Originally Posted by edunham
I notice that you do just as I do for old Brit brakes- Trident clutch cable...
As the two of us wrote in another thread:
Originally Posted by Magnetoman
Originally Posted by edunham
if you modified a Triumph Trident clutch cable...
That's an excellent suggestion. Since I own a Trident and know about its heavier clutch cable I'd like to think I would have eventually thought of this myself, but now I don't have to spontaneously think of it. Thanks.
Now that I've made a cable Stretch-O-Meter (patent pending) I eagerly await delivery of the package containing the Trident cables so I can measure their coefficient of elastostretchiness and then install them on the Catalina and BB.

Re: 1962 Catalina [Re: Magnetoman] #696505 05/25/17 7:46 pm
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My poor neglected Catalina has been sitting patiently for months waiting for some attention. Since it's a shame to have a bike 99% ready to ride I decided to take time from the 1928 Ariel to deal with the last 1%.

The Catalina had run really badly when I first fired it up last fall so since then I had rebuilt and remagnetized the magneto to eliminate it as a possible cause. I mentioned having done that in some other thread. I then completely disassembled and inspected the carburetor.

Even though the pilot jet wasn't blocked the bike acted as if it were so this time I looked at the pilot air passage under the microscope. I should have done that the first time I rebuilt the carburetor because I discovered a boulder blocking about half the passage (it was under the microscope so a piece of sand looks like a boulder...). It's always nice to discover a problem consistent with the symptoms, but I wouldn't know for sure it was solved until I tried to start it.

Since bikes like chokes I machined a bracket to hold a lever on the frame rather than on the already-cluttered handlebars. Then it took a few tries to get the free end of the cable the right length.

Ironically, when I came back in the house after finishing the choke installation the May issue of 'Classic Bike' was in the mailbox in which there is a how-to article on blanking off the choke hole because "The choke isn't usually necessary on Amal carbs." Right, another old wives' tale that magazine writers keep propagating.

Finally, with the carburetor installed and the tank replaced I decided to put some fuel in it to try to start it in the garage. At that point the nipple on the end of the compression release decided to come off. Anyway, with everything dealt with I tried to start it but I couldn't get a good swing because of where it was jammed in the garage.

The magneto was over a month ago but most of the above was over the past several weeks. Today I took the Catalina outside and put it on the DocZ rollers. It fired right up and I took a ~1 mile ride in the neighborhood. Even though the jetting needs some tweaking the clutch engaged and disengaged flawlessly and it's a rocket. I love the way that bike feels on the road, its sound, its power, its looks...

Back at the house I decided to drop the needle a notch and ride it again but, unfortunately, I realized I can't get the slide out without either removing the tank or unbolting the carburetor. But, since I hadn't yet replaced the air filter there was no point messing with the jetting so even though it's now only at 99.9% the Catalina is back in the garage waiting for the weekend for that last 0.1%.

Re: 1962 Catalina [Re: Magnetoman] #696516 05/25/17 8:47 pm
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That's great news magnetoman and yes I love the Catalina and surprised they don't carry quite the same premium as the 'street standard' goldie. By the way I may have located a Rudge Sport Special, but it's still early days yet! regards

Re: 1962 Catalina [Re: Dana_twin] #696526 05/26/17 12:09 am
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Originally Posted by Dana_twin
I love the Catalina and surprised they don't carry quite the same premium as the 'street standard' goldie.
The gap isn't huge, ~20%, but that it exists at all could be because all these years American buyers have been following the lead of the English who were deprived of access to Catalinas so they sung the praises of the only Gold Star they knew, the Clubman.

Typically models at the top of any marque's range are more sought after than other models. Catalina, check. Racing models sell for more. Again, check. And rarity definitely adds to price. With only 621 Catalinas vs. countless Clubmans, double check. I wouldn't be surprised if that price gap disappears in the future.

A Catalina is a much better choice for riding anywhere in an urban or semi-urban area, and there's only one road within 30 miles of my house where the riding position of a Clubman would give it a an advantage if there were a race. But, also within 30 miles are Forest Service roads where trying to ride a Clubman would be a nightmare but a Catalina would be great.

Originally Posted by Dana_twin
I may have located a Rudge Sport Special,
So many desirable bikes, so little room in the garage...

Re: 1962 Catalina [Re: Magnetoman] #707174 09/03/17 6:50 pm
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80% of carburetion problems are electrical...
... but that still means 20% are carburetion.

A Tale of Incompetence and Woe (but with a happy ending):

I wrote on May 25 that
Originally Posted by Magnetoman
My poor neglected Catalina has been sitting patiently for months waiting for some attention. Since it's a shame to have a bike 99% ready to ride I decided to take time from the 1928 Ariel to deal with the last 1%. ... Even though the jetting needs some tweaking ...
I understated the problem when I wrote "some tweaking." I could get the bike started in 2nd gear on the DocZ rollers (i.e. by spinning the engine pretty fast) and keep it running as long as I slipped the clutch and never let the rpms drop, because if it did drop below ~1500-2000 rpm I could only keep it barely going putt-putt-putt at a slow idle speed if I applied full throttle, with it not generating enough h.p. to increase the rpm again beyond that.

My notes show I had the carburetor completely apart three times since first starting the bike a year ago, and partially apart a few more times than that, measured the OD of the needle and ID of the needle and pilot jets to 0.0001", but it behaved like a problem with the pilot circuit. As noted in an earlier post, during one teardown under the microscope I discovered a grain of sand blocking the passage from the pilot jet to the main bore. I was sure that removing the grain would cure the problem, but it didn't. So, the Catalina continued to sit 99% done, but unrideable.

I returned to the Catalina a few days ago to try to get it ready for a long ride with a friend (with Plans B and C in case I failed) but it hadn't cured itself. I mentioned this in an email to Shane in Oz and he mentioned a number of things including asking if it had a needle with the correct taper. Well, this was the silliest suggestion anyone could have made since, after all, the guy who built the Catalina also built my BB Gold Star and a friend's ZB34/M20 hybrid, and he did an excellent job on both of those.

Having Shane's silly suggestion about the needle in the back of my mind I decided to switch carburetors completely using one of several 389 Monoblocs on the shelf. Yesterday I removed mine from the Catalina, leaving the slide assembly dangling from the cable, and then held a possible replacement assembly next to it to see if it had the same cutaway. Wait! What's this? The needle in the replacement is longer than the one on the bike!

All these months I had simply assumed it was the correct needle and hadn't checked the length (although I had checked the OD to 0.0001"). The one in the bike was a 'C' from the smaller series of Monoblocs, 0.37" shorter than the 'D' that is correct for a 389. I'd like to think I would have eventually discovered this myself, but after months of blithely assuming the needle was correct it was Shane's suggestion that focused my attention on it. Sigh...

Today the Catalina fired up immediately, ran great as I made two laps of the driveway, and even sat idling happily when I stopped in front of the garage. Finally, the Catalina is ready to start breaking in the engine, which will begin tomorrow.

In retrospect, I knew the previous owner was still rebuilding the Catalina when he died because most of the fasteners on the cycle parts were only finger tight. Although I knew the engine had run, because there was a circle of discolored oil in the center of the tank, I now realize that the size of the circle meant it had run only briefly. He would have had the same carburetion problem so he must have moved on to other parts of the rebuild after having problems getting it to run, intending to solve this later. I suspect I would have found the problem sooner had I only been working on this one bike, rather than scattering my attention among a number of bikes. Oh well, live and learn...

Moral #1. Assume nothing; check everything.
Moral #2. Some carburetor problems actually are carburetor problems.
Mroal #3. Multitasking can enhance productivity, but it also can make it harder to see some forests if the trees go by too fast.
Moral #4. It's your choice, but starter rollers are an alternative to knee replacement surgery.

Re: 1962 Catalina [Re: flowboy] #707239 09/04/17 8:21 am
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MM - from my ZB32 fault :-

So, 80% of carb problems are magneto, or is it 80% of magneto problems are carb? - Well, 100% of this carb problem was carb.
Following reset of magneto points, timing checks and brushes- no fault found
Removal of the carb- this time including strip down of the throttle slide - finds the needle had lost it's clip and was randomly lifting with the slide.
I replaced all and this time, I made a thin washer to fit between the end of the throttle spring and the needle clip.
Started and now running well


Is there a needle issue in general or are these 2 unrelated faults the exception.
The needle retention clip for the Concentric is affected by the way the spring sits on it.

I have filed a thin washer to a shape that fits over the needle top and cable (similar to a Japanese carb)- leaving a seat for the spring to sit against - I hope that this stops further problems down the road.

I had the carb off a few times but failed to separate the needle and throttle slide - because it obviously couldn't be a needle fault could it.

Looks like 80% of carb faults are magneto or vice versa or co-incidence or all of the above

Moral #4. It's your choice, but starter rollers are an alternative to knee replacement surgery.
OR
have a 350 after the age at which your knees are likely to give out


David C

Re: 1962 Catalina [Re: Magnetoman] #707276 09/04/17 3:30 pm
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Originally Posted by David Cass1
So, 80% of carb problems are magneto, or is it 80% of magneto problems are carb?
To be clear, this fundamental law of physics applies to all motorcycle carburetors and electrical systems, not just Amals and magnetos.

Originally Posted by David Cass1
Is there a needle issue in general or are these 2 unrelated faults the exception.
Hmm, that's an interesting question I hadn't considered before. Now that you mention it, the needle is special.

The slide moves in operation because it has a direct mechanical connection to the cable. If the cable moves, so does the slide. If the cable breaks, you immediately know it. Bench testing determines if the slide has too much or too little clearance, and after bolting the carburetor to the engine simply operating the twist grip or lifting the slide with a finger confirms the flange hasn't distorted to cause binding.

In principle, at least, the sizes of the three jets (pilot, needle, and main) can be determined from the numbers stamped on them as well as inspected for blockage on the bench. There have been vexing problems with quality control over the years so the numbers can't necessarily be trusted without confirmation, but once assembled and bolted to the engine (and assuming the pilot jet doesn't become blocked) they won't change, at least in the short term. The needle jet does slowly enlarge so it is a wear item that has a significant effect on performance, but that happens over thousands of miles.

The needle, however, is special because, unlike the slide, if its mechanical connection is broken (e.g. the clip comes off) it isn't easy to spot. Again, assuming a jet or passage doesn't become blocked with sand or varnish from fuel left in the bowl, the needle is the only component on the carburetor that can "change" in service, and change in a way that isn't easy to spot from the outside.

In my case it wasn't that the needle changed, it was that I failed to check if it was the right length. I checked the pilot jet, needle jet and slide cutaway to confirm they had the sizes marked on them, and the OD of the needle to make sure it was correct, but I didn't check the length. I only have myself to blame since I know AMAL needles come in different lengths, tapers, and even diameters. Moral #1. Assume nothing; check everything.

Originally Posted by David Cass1
Moral #4. It's your choice, but starter rollers are an alternative to knee replacement surgery.
OR
have a 350 after the age at which your knees are likely to give out
Eighteen months ago an Australian loaned me a 350 Gold Star for a day. It was the only time I've ridden a 350, and I don't know the CR of the piston in it, but I don't remember it being noticeably easier to kick over than a 500. I've mentioned this before, but 15 or so years ago, to extend his riding life, Eric Cheney built a Triumph 350 twin for Bud Ekins using pistons of such low compression that it was possible to start the engine by operating the kickstarter with your hand.

It's not that rollers are an affordable option for everyone, or a solution for every situation (e.g. you can't take them with you on a ride), but they are invaluable when troubleshooting a bike that is reluctant to start.

Re: 1962 Catalina [Re: Magnetoman] #707313 09/04/17 8:28 pm
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Today is a holiday in the U.S. (Labor Day, celebrated in Sept. so as not to be confused with May Day) so I waited until after 10am to start the Catalina. After my two laps of the driveway yesterday I put the air cleaner back on since I want to sort out the jetting with the filter in place. The air cleaner should make it run richer and indeed even at driveway speeds it ran worse than today than yesterday.

I managed a couple of miles on it but it would 4 stroke when I gave it any throttle so it's too rich. Even when slipping the clutch it didn't have enough power to bring me up my long, steep driveway so I jumped off and ran beside it in the 95-deg. heat until it died (and I felt like I would) just before cresting the top. Boy, was that hard work.

It's jetted now according to AMAL's specs for a "Gold Star Scram. (Export)." In particular, the slide has a 3 cutaway and the needle is on the 2nd slot. However, the AMAL list for 1961 shows "B34 Scrambler (U.S.A.)" which presumably is the Catalina with its unique air filter. The list shows a 4 cutaway (leaner) and the needle on the 4th slot (richer). So, the Catalina is back up on the lift waiting me for me to recover from my ordeal and search my collection of slides in the hopes I have a 4.

By the way, handy as a Harbor Freight lift is, the recent daily foot pump routine is getting old (91 pumps to get it to full height, but who's counting?...).

You know how even before you send something, sometimes there are things you write that you know you shouldn't send, but you hit 'send' anyway? That applies to the next paragraph.

The oil I'm using to break in the Catalina is Valvoline 20W-50 4-Stroke Motorcycle Oil, SG rated as per John Healy's advice, along with 4 oz. of Lucas TB Zinc Plus. This oil has 1120 ppm of Zn and the Zinc Plus increases that by 2850 ppm/2 qts. (the capacity of the Catalina's tank) to a total of 3970 ppm. Based on its name I looked into Lucas "Engine Break-In Oil" but I was unable to find any information on its rating or additives other than Zn content (3500 ppm). After I put, say, 300 miles on the Catalina, and assuming it appears the rings have seated, I'll switch to 50W Valvoline VR1 (1300 ppm Zn), again with 4 oz. of Zinc Plus, for a total of 4150 ppm.

I hope the above doesn't cause this to degenerate into another dreaded oil thread. I only wrote it in case anyone cares to know what I decided to do to break in this engine. End of oil discussion.

p.s. messing with the needle and slide isn't easy with this bike, since the air cleaner assembly has to come off (two locktited knurled nuts plus three bolts) and the oil tank strap loosened so the tank can be moved to barely allow the carb to clear the studs. That's why it's back up on the lift rather than me kneeling on the concrete floor.

Last edited by Magnetoman; 09/04/17 8:43 pm. Reason: p.s.
Re: 1962 Catalina [Re: Magnetoman] #707440 09/05/17 9:41 pm
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As an update, I won't have a chance to start the Catalina again until tomorrow, or possibly Friday. But, I found several 3.5 slides on the shelf so I scribed one of them with my calipers for the extra relief needed to turn it into a 4. Looking at my range of choices for removing the material I decided on a grinding stone in the drill press. It took only a few minutes, including cleaning the burrs, and it looks like it came from the factory. I checked the height when done and it's 1/4" to within at least ~0.01"

The new slide was slightly out of round near the base (~0.01"). However, I have a set of two-piece dies I made a few years ago having the IDs of the various AMAL slides so I found the right one and pressed the slide with it in the vise. After doing this just once the out of round was reduced to ~0.001".

I installed the modified slide, clipped the needle on slot #4 and bolted the carburetor and air box back in place, testing that the slide operated without binding. However, given how rich it seemed to run I suspect the air cleaner element may be causing a huge restriction. So, on order for delivery tomorrow is a sheet of air cleaner foam that I'll cut into the two 4"x4" sections to slot into the box. I have coarse stainless screen that I'll also cut into 4"x4" sections to provide the support for the foam.

Offline someone suggested the air box assembly itself might represent a significant restriction independent of whether or not filter material was in place. Simplifying a bit, the conductance of a tube for room pressure air goes as the fourth power of the tube's diameter divided by its length, and the total conductance of tubes in series adds like resistors in parallel.

With its cover removed, at full throttle the Catalina's air box is essentially a 9"-long x 2-1/2" ID tube in series with the 4"-long x 1-3/16" ID of the carburetor and intake tract. So,

Conductance airbox = G (2.5")4 / 9" = G x 4.34

where G is a constant.

Conductance carburetor = G (1-3/16")4 / 4 = G x 0.50

Hence, the relative conductance of the airbox is Gx4.34 / Gx0.50 = 8.7x higher than that of the carb. alone. Therefore, the presence of the airbox (minus cover and filter) reduces the overall air flow through the system according to:

1/Total = 1/Box + 1/Carb = 1/4.34 + 1/0.5 = 2.2304

so Total =0.448, i.e. flow is reduced by 10.4% from that of the carb. alone at full throttle.

At, say, half throttle the open area of a ~1" length of the carburetor (i.e. under the slide) is reduced to ~0.6"-dia. so because of the dia.4 dependence the relative effect of the air box is much less than half of 10.4%. In any case, this shows the additional restriction of the box assembly, minus cover and filter, is small for all throttle openings.

It's more complicated with the cover in place because it is held off the main box with a 0.33" gap around three of the edges so this opening is better represented as an orifice rather than as a tube. The length of the opening is 16.5" so the total inlet area is 5.45 in.2. Oversimplifying this rectangular annular gap as being a simple circular orifice (which isn't as silly as it might seem, although I won't go into the details), it corresponds to a circular hole of diameter 2.6". Obviously, a plate with a 2.6"-dia. hole held in front of the 1-3/16" inlet to the carburetor would have no effect on the flow. Turbulence has been neglected in all of this, but the results for the air box are so much larger than for the carburetor that we won't worry about such trifles...

The above (simplified) calculations show that the restriction on the air flow through the entire Catalina filter assembly is almost entirely due to the 32 in.2 of the filter material itself. This is 33% greater than the surface area of a "standard" round AMAL filter assembly like on my Triumph 500 (5" dia x 1-1/2" deep = 24 in.2). As this shows, BSA made sure a Catalina's top speed would be limited only by the rider's wrist, not by the engine's air intake.

Re: 1962 Catalina [Re: Magnetoman] #707555 09/07/17 1:35 am
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--delete duplicate post--

Re: 1962 Catalina [Re: Magnetoman] #707557 09/07/17 2:02 am
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Originally Posted by Magnetoman
As an update, I won't have a chance to start the Catalina again until tomorrow, or possibly Friday...
After reconfiguring the carb. yesterday, today I removed the filter element from the airbox and started the bike on the rollers. It ran like crap, although when the revs built up it sounded much better. The plug was sooty and wet and the inlet to the carb was wet with fuel.

Having carefully... no, make that very, very carefully, assembled, measured, and inspected every aspect of this carburetor the two most logical explanations for the problem at low speed were that 1) the cams are mistimed, or 2) the carb. came with a hex on it that wasn't BSF. A third explanation, electrical, was less plausible not only because I had rebuilt the magneto myself but whenever the engine was barely running it ticked over regularly at what I estimated to be only ~250 rpm. That argued against a problem with the magneto.

Anyway, mistimed cams seemed the less likely of the two given the builder's excellent work on at least two other bikes, leaving the most probable scientific explanation that there is a curse on the carburetor. Since everyone knows you should only change one thing at a time when diagnosing a problem, the one thing I decided to change was the entire carburetor. I used another 389 body to build up a replacement carb using none of the pieces from the cursed carb. Well, not quite none. I used the slide I modified yesterday along with the needle now in it because neither of those came with the original carb.

Not that it matters for function, but I picked a carb body stamped 389/13 because that was used on Gold Star scramblers, albeit not Catalinas. It has a 1-5/32" bore, ever so slightly smaller than the 1-3/16" of a Catalina. The slide was a tight fit so I checked and found a very slight bow on the mounting flange. Once I flattened that with a jig (i.e. bent it flat, not ground it flat) the distortion was gone and the slide went smoothly in without problem. I used a brass float and Viton-tipped needle, and when I checked the level it was right at the dot below 'AMAL'.

Although after bolting it back on the engine I was out of time to do any more work on it today, I couldn't stand the suspense so I took the bike out of the garage, started it, and circled the driveway a half-dozen times. The engine had been completely transformed by the replacement carb, even though in every way (other than the curse) it was identical to the carb it replaced. I put the bike back up on the lift to reinstall the airbox and cure a tiny leak due to not having replaced the gasket at the main/needle jet holder. When I came into the house my wife asked what I had done to it because "it sounded completely different." Unless something comes up, on Friday I'll venture further than the driveway.

With evidence like these two identical carburetors, how could a scientist not be superstitious?

Re: 1962 Catalina [Re: Magnetoman] #707575 09/07/17 9:50 am
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So it isn't just me........ crazy

I went thru a similar exercise in frustration with a 389 on a twin. One cylinder was fine, the other was a mess. No matter what I tried, one cylinder would not settle down and run correctly. Since it was a twin, I just swapped the carbs. When the good cylinder now became the bad cylinder, was enough for me. Built up another 389 from the stash and replaced the crap carbie. Problem solved.

I had a lot of similar symptoms with that carbie. No one will ever have to deal with that body again laughing



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Re: 1962 Catalina [Re: Rich B] #707577 09/07/17 10:19 am
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I had a lot of similar symptoms with that carbie. No one will ever have to deal with that body again laughing

Sleepin' with the fishes eh!

Re: 1962 Catalina [Re: David Cass1] #707637 09/07/17 8:41 pm
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More like blunt force trauma.......

Zinc body, sledgehammer, I know who is winning that battle

laughing


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Re: 1962 Catalina [Re: Rich B] #707641 09/07/17 9:27 pm
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Originally Posted by Rich B
sledgehammer,
My desire to figure out what is is wrong with the original carburetor is tempered by my current desire never to see that carburetor again as long as I live. However, curiosity has a way of winning with me so I attached a label and replaced it in the box with the other 389s. Although Voltaire wisely wrote that 'not everything that needs explanation, merits explanation', I've not always been able to heed his advice. For the foreseeable future, though, that carburetor is dead to me.

Re: 1962 Catalina [Re: Magnetoman] #707651 09/07/17 11:54 pm
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There was a time when I would have: 1.) spent a stupid amount of time and energy to make it work 2.) spent a stupid amount of time and effort to understand why.

Now, I find I don't have the time or inclination to make it work or understand why. Fix it and move on. Guess I am getting lazy laughing

Or I would rather ride more and fix less : bigt


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Re: 1962 Catalina [Re: Magnetoman] #707757 09/08/17 8:47 pm
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First, before getting to the good stuff, who sells the best (correct size, longest lasting, best sealing,...) fork oil seals? One fork leg weeps and now is the time to take care of that.

As we left things yesterday, the replacement carburetor had completely transformed the bike, but it was back up on the lift to cure a tiny fuel leak and install the air box. The leak turned out not to be from the jet holder, but from a slightly warped float bowl cover, so I swapped it for another (not, though, taken from the jinxed carburetor).

Digression: Why is it that all 389 gasket sets contain a too-small fiber washer for the jet holder? The OD of the holder is 0.671" but the fiber washers are 0.640" ID. They're rigid fiber, not flexible O-rings, so they simply won't fit. I gripped one of them in a six-jaw collet and drilled it 11/16" (0.688"), but what do people do who don't have lathes, collets and 11/16" drill bits? More to the point, why don't retailers insist their suppliers give them the right kits to sell rather than continue to sell kits they know won't work (unless I'm the very first person ever to need this fiber washer and discover this problem with aftermarket kits)? End diatribe.

After fixing the leak by using a different cover along with a new gasket and EZTurn petcock lube as gasket sealer, I decided to see if there were any major carburetor issues before bolting the airbox back on. I lowered the lift and wheeled the bike out of the garage, and then bravely decided to try without the rollers (which were still in the garage). Tickled, ~1/4 choke, ~1/3 retarded, and eased past TDC. It started on the first kick! I savored the sound for a few moments then rode it to a shady spot, shut it off, and went inside to get my helmet and jacket.

When I came out I repeated the ritual and it again started on the first kick. I then headed out for an ~8 mile ride. I didn't go further today because there was less than a gal. of fuel in the tank and I didn't want to risk running out before reaching the nearest station. Actually, the route would have been ~12 miles but there was a police car hiding in the bushes next to the major street I would have had to accelerate onto next and I didn't want to risk breaking his decibel meter. So, when I saw him, I did a U-turn and stayed on the neighborhood streets.

The bike ran great. What a difference an identical carburetor makes...

When I got back home I adjusted the mixture and slide screws before shutting it off and putting it back on the lift to install the air box and oiled-foam filter material. Later today I'll get another 2 gal. of gasoline so that tomorrow I can venture even further.

I love it. Everyone should have a Catalina.

Re: 1962 Catalina [Re: Magnetoman] #707779 09/09/17 12:15 am
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Awesome! And congrats. beerchug :bigt

I don't have a Catalina, but I do have a DB/DBD hybrid with scrambler cams. I am prejudice, but I find that an awesome combination on the twisties of this part of Ohio......


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Re: 1962 Catalina [Re: Rich B] #707837 09/09/17 5:01 pm
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Originally Posted by Rich B
a DB/DBD hybrid with scrambler cams. I am prejudice, but I find that an awesome combination on the twisties of this part of Ohio.
I haven't had the engine open so I don't know what cams are in my Catalina but I assume they are scrambles as well (65-2446 for both). Interestingly, that's also how the Special Competition model was configured by the factory, making these bikes more responsive than Clubmans over a wider range of throttle openings. For the riding I do in my dotage having a lot of h.p. over a wide rpm range is better than having a few more h.p. but only at WOT.

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