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Re: 1962 Catalina [Re: Magnetoman] #737267 05/31/18 10:56 pm
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Sorry to hear about your riding woes but at least everyone seems to be OK, just one of those things I guess.

Regarding the gummed up carb slide, maybe one possibility is that the the fuel tank has been sealed at some point in the past with a non ethanol resistant sealant which is now slowly breaking down. Alternately a similar problem may happen if the tank is fibreglass.

I note that you are using a foam air filter and would like to offer some advise which you are likely already aware of but for safety's sake I will repeat. Foam air filters can be the source of fires especially if you experience kickback or spitback through the carb. The problem is made worse if oil or fuel has leaked onto the filter and the filter is old. A while back my B44 caught fire whilst using a foam air filter when I experienced kickback. I was lucky as I was able to extinguish the fire after a few seconds using my gloved hands, any longer and the whole bike could have gone up in flames.

I believe some foam air filters are resistant to fire and better still are the K&N style filters which use cotton as a filter medium together with a stainless steel mesh which in combination make the risk virtually zero.


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1967 B44 Shooting Star
1972 Norton Commando
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Re: 1962 Catalina [Re: Magnetoman] #737280 06/01/18 12:40 am
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Originally Posted by gunner
Sorry to hear about your riding woes but at least everyone seems to be OK, just one of those things I guess.
If an accident had to happen, it was the best I could have hoped for. Damage to my friend was enough to give us something to remember the ride by, but not enough to last beyond a couple of days. Of course, of far less importance than damage to people is damage to the bikes. The BB appears to have suffered only cosmetic damage and the Matchless looks as good as ever (although, its beauty may turn out to be only skin deep...).

The bikes are off the truck and in the garage now. Over the weekend I'll drain the fuel from both (and the oil from the Matchless before its leaky oil pump does it for me) and examine the BB more closely. The only thing I can see that I'll have to order are new footpeg rubbers. Everything else I either have (replacement Chronometric glass), or it looks like I can fix with a little labor plus paint.

I should have put in a plug in for properly rebuilt magnetos in my post yesterday. For the Matchless I had to take the battery off the charger, add water because I hadn't noticed it was getting low, open the cover, wire it into place, and close the cover. The bike acted like it was somewhat inclined to start on the first kick, but it wanted me to kick harder than I did. After three wimpy kicks we pushed the bike and it started almost instantly. In contrast, after sitting unused for six months the Gold Star simply started on the first kick. I hate batteries.

Originally Posted by gunner
Regarding the gummed up carb slide, maybe one possibility is that the the fuel tank has been sealed at some point in the past with a non ethanol resistant sealant which is now slowly breaking down.
No, the inside of the tank is bare steel.

Originally Posted by gunner
Foam air filters can be the source of fires
Thanks for mentioning this. Unfortunately, I was unable to find any filters that would fit in the Catalina's air box which is why I custom cut my own from foam.

Re: 1962 Catalina [Re: Magnetoman] #737384 06/02/18 5:35 am
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Hi MM I´m sorry to hear about your mishap and I hope your friend arrived ok after such a long flight back.

Saludos

Re: 1962 Catalina [Re: sanarthur] #737475 06/02/18 11:39 pm
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Originally Posted by sanarthur
I hope your friend arrived ok after such a long flight back.
I got an email from him earlier today saying he arrived back in Napoli on time and with "almost no traces of the accident."

Today I removed the battery and drained the fuel and oil from the Matchless, so it's now officially in mothballs for the foreseeable future. I then drained the fuel from the BB and turned my attention to the Catalina's sticky slide. Repeat after me, correlation does not necessarily imply causality.

I removed the jet block and thoroughly cleaned it, the wall of the main body, and inside and outside of the slide. Nothing felt sticky before I did this although the paper towels removed quite a bit black residue from various surfaces. However, after I bolted the jet block back into place (it's held down by the jet holder) the slide was very stiff, although slightly loosening the jet block freed it up. I disassembled, reassembled, and repeated this a few times getting somewhat different results each time varying from being a little tighter to being much tighter after I tightened the jet block.

Since this was consistent with the base of the jet block being slightly tilted with respect to its seating surface in the carburetor body I put the jet block in the lathe and ended up skimming about 0.003" from the seating surface before it was perpendicular to its walls. The photograph shows it after the first ~0.001" or so had been removed. After I did this and reassembled the carburetor the slide was smooth as silk. The black residue had been a red herring.

In retrospect this all makes sense. At least once in the past after assembling the carburetor there was a noticeable 'catch' in the movement of the slide at low throttle settings that was quite annoying. But, it went away as I fiddled with the jetting. Each time I changed the main jet I could easily change the torque on the jet holder that clamps the jet block in place. Since there was a slight tilt to its bottom surface different torques resulted in slightly different amounts of tilt of the top of the jet block, changing the clearance between it and the carburetor body. After my final jetting run last fall during which the carburetor behaved well I drained the fuel from the carburetor. In retrospect it is now clear that I changed the torque on the jet block as well when I re-tightened it. The jet block also had six months to slightly settle, which could have been a factor as well. Mystery solved.


Attached Files JetBlock.jpg
Re: 1962 Catalina [Re: Magnetoman] #737506 06/03/18 7:35 am
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Well spotted. I'd like to think I'd find and correct a problem like that!

The bigger question in my mind, is why was there a problem in the first place?


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Re: 1962 Catalina [Re: Magnetoman] #737541 06/03/18 4:14 pm
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Originally Posted by Kerry W
The bigger question in my mind, is why was there a problem in the first place?
The Catalina was from the same guy who built my lovely BB Gold Star and friend's lovely ZB34/M20 bitza who all evidence indicates was an excellent mechanic (an electrician, not so much...). However, unlike the BB, the Catalina wasn't finished when he died, and the carburetor(s) have caused more than their fair share of grief.

Looking back through my notes, despite finding and correcting various issues (e.g. it came to me with a short 'C' series needle in it rather than the correct 'D' series) I still had trouble getting the bike to run at all. I later determined a major factor was too much back pressure from the silencer I had added to the open pipe, but a few days before discovering that I "Built up a completely new 389 carburetor using none of the components from the current carb. except the needle and 4 cutaway slide. Brass float, viton needle, and proper float bowl height. It transformed the bike." Twelve days, and five entries in my notes, later I wrote "Carb no longer has tight spot." Although the intervening notes don't mention the tight spot it's clear the issue due to the slightly tilted throttle body has been there ever since I built that carburetor from parts.

So, finally, getting to your question. Of course, there's no way to know the history of that jet block. It could have come out of the casting mold that way, been slightly "mis-chucked" in the factory lathe if there was a subsequent machining operation, slowly distorted over time due to certain of Zamak's issues with dimensional stability, or abused in some way by previous owners. I tend to think abuse wasn't the cause since, although 0.003" doesn't seem like much, that's actually a lot of material to have been displaced when there are no signs of abuse.

Re: 1962 Catalina [Re: Magnetoman] #751520 10/04/18 5:41 pm
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Where I left off this thread the Catalina was, as far as I know at this point, 100% ready to go, although thanks to working on the Ariel I haven't ridden it since last fall. The BB, on the other hand, has been sitting mostly untouched on the lift since it slid down the road four months ago. Luckily, the damage to the BB was cosmetic and not very severe. So, no longer facing a hard deadline with the Ariel I turned to the BB.

The back corner of the seat was slightly torn. I filled in the tears with black 'Shoe Goo' which didn't return it to as-new condition, but it will do on a bike intended to be ridden. As with the other damage, all of it is on the left side of the bike.

The tank had two chips in the paint, exposing red primer. I filled the chips with Testors metallic silver. Again, not perfect, but it will do. The photograph doesn't do justice to the color match which is pretty good, although not perfect (e.g. the one at the lower right actually is the same silver as the other one, not brown). Also, I haven't sanded them yet to eliminate the three-dimensionality which currently makes them stand out more than they eventually will.

The headlamp bezel was bent and scraped, although the glass survived. I simply swapped the bezel for another I happened to have. Both headlamp mounting ears on the forks were bent but they were easy to bend back into position.

The mount for the speedometer was bent upwards and paint scraped off quite a bit of the outside of the case, but the glass survived. In contrast, the mount for the tachometer wasn't bent and the paint was untouched, but the glass was broken. Since the speedometer had been acting wonky at speeds above ~50 mph I used the opportunity to remove the mechanism and use spray degreaser on the old grease inside, removing most of it. This wasn't the first time the speedometer had been apart as evidenced by red silicone serving as a gasket. I then reoiled the mechanism using Starrett Tool and Instrument Oil and sprayed the case with gloss black, not taking pains to do anything like a perfect job. I degreased and oiled the tachometer as well, replacing its glass with one cannibalized from another one.

The gearbox was 90 cc low (out of 400 cc) so I topped it up, but the primary case was full. I drained the oil tank, attaching several prominent notes to the bike to that effect, and will wait until I next have a chance to ride it before adding fresh oil. Also, I have a Burgess-shaped silencer to replace the current twitter-type but won't make that swap until I'm ready to ride because once I make the switch I'll likely have to play around with the jetting.

In the hopes it solves the issue of a false neutral between 2nd and 3rd I fully tightened the plunger spring, compressing it ~1/4" further than it had been. If that doesn't solve it, and probably even if it does, longer term I plan to rebuild an STD.T gearbox and swap it for the unmarked one currently in the bike.

Attached Files Seat.jpgTank.jpgHeadlamp.jpgSpeedometer.jpg
Last edited by Magnetoman; 10/04/18 6:25 pm. Reason: added info. about false neutral
Re: 1962 Catalina [Re: Magnetoman] #751567 10/05/18 12:30 am
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And this, from the man who has decried bodgery in the past! facepalm
With age, comes wisdom.
Welcome to the "git 'er done" base. laughing

And a bit of material science in the bargain. Who knew, Shoe Goo. thumbsup

JR

Re: 1962 Catalina [Re: Magnetoman] #751573 10/05/18 2:33 am
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Originally Posted by Jerry Roy
And this, from the man who has decried bodgery in the past!
OK, OK, I admit the seat repair isn't pretty. But in defense of the sanctity of the word "bodge," shouldn't it be reserved for repairs that are cheap and easy and worse than a proper repair? Given the variety of small tears and punctures, short of having the seat recovered, I can't think of a way to properly repair it. Further, the Shoe Goo at Ace Hardware was more expensive than their black silicone. I realize I'm drawing a fine distinction, and I'll accept the verdict of the jury, but I plead 'no bodge', your honor.

Attached Files ShoeGoo.jpg
Re: 1962 Catalina [Re: Magnetoman] #751685 10/06/18 12:45 am
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Originally Posted by Jerry Roy
And this, from the man who has decried bodgery in the past!
When I got my BB Gold Star almost four years ago the builder's notebook said he couldn't solve the problem of too much oil coming from the breather and so he had run a hose from it along the inside of the rear mudguard to as far back on the bike as possible. Clearly, this was a bodge. However, I thought I might have a solution to this problem so as a test I bodged together a temporary catch tank from PVC pipe and end caps filled with Cu mesh from a kitchen scrubbing pad. I then temporarily zip tied it in place under the seat.

The tube from the breather enters at the bottom of the catch tank and my hope was the oil vapor would condense back into liquid on the Cu mesh and the liquid would then run back down through the breather tube into the timing cover. I T'd the oil tank vent into a tube at the very top to take anything that made it that far back down to the ground.

The proof of concept worked great, with never a drip under the final outlet tube, but the temporary bodge remained in place. However, shamed by Jerry Roy, today I did what I have been planning to do ever since the "temporary" catch tank proved the concept. I welded a non-bodge version from a 3-1/2" length of thin wall 1-3/8" Al tubing, filled with the same Cu scrubbing pad mesh, and with proper fittings at either end for the inlet and outlet. After I polish it I'll make an appropriate bracket and mount it to the frame, bringing to an end this bodge.

Attached Files CatchTank.jpg
Re: 1962 Catalina [Re: Magnetoman] #751696 10/06/18 2:47 am
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Huuuummm, that's interesting.
So, are we to take away from this that a high polish changes a bodge to development engineering? confused

And speaking of pot scrubbers, did you ever pack your muffler with said items?





Can you hear me now? cool

JR

Last edited by Jerry Roy; 10/06/18 2:50 am.
Re: 1962 Catalina [Re: Jerry Roy] #751746 10/06/18 4:58 pm
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Originally Posted by Jerry Roy
So, are we to take away from this that a high polish changes a bodge to development engineering?
Now, now Jerry Roy, behave yourself.

Re: 1962 Catalina [Re: Magnetoman] #751782 10/07/18 1:28 am
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Ooops, I should of put a laughing emoji behind that question.
All in good humor, Doc

All levity aside, did you ever come up with something that toned down the muffler?

JR

Re: 1962 Catalina [Re: Jerry Roy] #751803 10/07/18 4:00 am
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Originally Posted by Jerry Roy
did you ever come up with something that toned down the muffler?
Basically, I ignored everything but the Ariel for the past year so I didn't even give a thought to the sound. I'll have to ride it again to remind myself what it was I wanted to deal with. Maybe it will sound better to me this year.

Re: 1962 Catalina [Re: Magnetoman] #762555 01/14/19 4:28 pm
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Look what I found when straightening up the garage in the aftermath of the SCT2 gearbox rebuild documented starting here in the Spitfire thread. Normally these electrical disconnects are only found under rocking horses, but I found it on a shelf of Gold Star parts. This makes me wonder what else I have that I don't know about...

I'm starting to arrange a Gold Star Ride for later this spring with my Cannonball teammate as well as to let a friend who is rebuilding a Catalina, but who has never ridden a Catalina, ride a Catalina (shh, don' t tell him, but my hope is he will hate it so much he'll pay me to take it off his hands). This will be the first long ride with the Catalina after the ~1200-mile ride in Texas a year ago.

Aside from routine maintenance after that Texas ride, including replacing the needle jet that had completely worn out in just 1200 miles, upgrades made as a result of the experience include rebuilding and installing an ASCT gearbox in place of the SCT, increasing the overall gear ratio by changing the engine sprocket from 18T to 21T, lengthening the gearshift lever to make it the same from the footpegs as on other bikes, and installing a new pair of Hagon shocks. This should bring the Catalina to a near-ideal configuration.

Attached Files Headlamp_disconnect.jpg
Re: 1962 Catalina [Re: Magnetoman] #762619 01/15/19 4:19 am
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Going back to the oil 'bodge'...I think the original bodge was made by BSA, by retaining the useless flapper valve in the OHV engines! It might have been fine pre-war, in an M20, but the only real solution is the rotary breather. Turning a flapper valve timing cover into a rotary breather version solved similar issues for me...
KW


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Re: 1962 Catalina [Re: Kerry W] #762701 01/16/19 9:47 am
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Originally Posted by Kerry W
Going back to the oil 'bodge'...I think the original bodge was made by BSA, by retaining the useless flapper valve in the OHV engines! It might have been fine pre-war, in an M20, but the only real solution is the rotary breather. Turning a flapper valve timing cover into a rotary breather version solved similar issues for me...
KW

No they are not fine in an M20 either.
Works well from idle to around 3500.
After that it works backwards and ends up blowing oil out the unsealed main , filling the primary.

The flapper is a throw back to the pre-war long stroke, slow reving engines with no oil seals.
The idea of running negative pressure in the crankcase was to promote air entering via the scrolls & slingers holding the oil in.

Rex did a lot of work on breathers you can find most of the work in his blog pages or in the 2 books he published.
Down side they are both e books so you need a kindle or kindle reader to access them.

The same data is burried in his personal blog but that is more contorted than mm's ariel thread (https://bunnbreather.wordpress.com/tag/bunn-breather-kit/)

Last edited by BSA_WM20; 01/16/19 9:50 am.

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Re: 1962 Catalina [Re: Magnetoman] #778995 07/18/19 1:39 am
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This afternoon gave me an opportunity to photograph two bikes in their current configuration as I switched their positions in the garage in preparation for instrumenting the Catalina for air/fuel measurements in order to make its already-perfect mixture even perfecter. Also, for the engine simulation program I want to determine how well the airbox filter arrangement flows, and I'm also curious how well the present shorty silencer flows.

Different strokes for different folks, but if I were to build the perfect-for-me Catalina it would be exactly like the one in the first composite. Modifications I made as a result of our 1200-mile ride across Texas in the fall of 2017 brought it to perfection. What might not be noticed is I lengthened the gear shift lever from its too-close spacing on a standard Catalina. What can't be seen is after Texas I installed an ASCT gearbox, which is proper for this 1962 Catalina anyway, giving it a lower 1st, but the same 2nd-4th, as an SCT. However, I also installed the larger "Clubman" engine and gearbox sprockets to make it less buzzy in 4th on long stretches of road in the great southwest. So, 1st and 4th give it the best of both off and on-road riding, which is something I want for the desert highways, mountain roads and fire trails of the southwest.

Similarly, if I were to build the perfect-for-me cafe racer it would be just like the one in the second composite. The Competition's h.p. is more than sufficient to greatly exceed every speed limit in the State, the SCT gearbox is my favorite one for all-around riding, the 1036 Concentric gives it a civilized idle as well as excellent performance, and the Eddie Dow TLS front brake, relined and arced to the drum by Vintage Brake, stops the bike almost as well as a disk. Also, the seating position is very much like that of my Ducati Monster which, for me, is a good thing. As NYBSAGUY experienced on the east coast a week or so ago, 40 miles of dirt road riding on a Monster is quite possible, whereas even one mile on a bike with clip-ons would be a nightmare

As an aside, it's interesting how very different it feels to sit on the Catalina than on the Competition. They're 95% the same motorcycle, but that last 5% makes a world of difference. I should add that although the configurations of these two bikes are perfect for me and how I use them, they well could be completely wrong for someone else.

The third composite allows easier comparison. The location of the handlebars is the most apparent difference, but closer inspection shows the foot peg is at at the front of the gearbox on the Catalina, but somewhat below and behind the swinging arm pivot on the Competition. Together, these make for significantly different riding postions.

Attached Files Catalina_1962.jpgCompetition_1963.jpgCompetition_Catalina.jpg
Last edited by Magnetoman; 07/18/19 2:01 am. Reason: added third photo
Re: 1962 Catalina [Re: Magnetoman] #778999 07/18/19 2:37 am
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Great illustrations, MM. I can only hope that one day my Catalina will look half as good as yours. If I can wrestle its head off your flow bench, that is. It will never run as well, of course, but I will simply blame you.


1949 BSA ZB34 'Bitsa'
1959 BSA DBD34 Catalina
1973 Norton Commando 850 R
1974 Norton Commando 850 R (I know, one too many)
1975 Honda TL250 Trials, a new addition to the family
1998 Montesa Cota 315 HRC
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Re: 1962 Catalina [Re: Magnetoman] #779342 07/22/19 2:22 am
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In the spirit of nothing exceeds like excess, I upgraded my perfectly fine AFR system to the next level. I'm now instrumented to log, for up to 566 hours continuously if so inclined, the AFR, throttle position, rpm, acceleration, and exhaust gas temperature. I have one unused position on the data logger so could add road speed with another sensor, but that would be excessive... or, would it? Hmm...

When I installed the modified Clubman 'AFR pipe' on the Catalina I discovered a perforated baffle inside the Catalina's pipe that I didn't know was there. It hadn't become separated from the present silencer because it's too big to fit inside. I can't imagine how it could have been left behind by the silencer that departed on our 2017 Texas ride so maybe it was put there by the previous owner(?). It's a mystery.

Anyway, when I previously adjusted the jetting to be perfect it was with the extra baffle in place, and since I'm not particularly fond of annoying the neighbors any more than necessary, I fished it out and put it in the 'AFR pipe' before installing the shorty silencer. The slightly larger restriction due to the sharp bends of the Clubman pipe will be partially compensated by the lower restriction of the shorter pipe so, overall, the efficiency of the exhaust system should be pretty close to what it will be when I put the Catalina pipe back on. Hence, the jetting I determine with the setup in the photograph should be the same as with the Catalina pipe.

Unfortunately, my elongated shifter interferes with the Clubman pipe so I'll have to install a standard one for these tests (the shifter is barely held on the end of the spline but is touching the shaft in the photograph).

Since the jetting of the Catalina's Monobloc is already perfect, getting it perfect-er should go faster than starting from scratch with a 2-stroke 1038. But, I'll spend some time getting used to the new instrumentation. The weather looks like it will cooperate for a ride early in the week by dropping to the low 100s (even as low as 99 on Monday), but I'm conflicted between jetting and measuring the air flow of the filter. I don't want to put the air filter box back on just to take it off again.

Attached Files Catalina_AFRsetup.jpg
Re: 1962 Catalina [Re: Magnetoman] #779344 07/22/19 4:17 am
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Put a rear-set footpeg on it for the trial duration?

Last edited by Kerry W; 07/22/19 4:18 am.

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Re: 1962 Catalina [Re: Kerry W] #779346 07/22/19 5:15 am
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Originally Posted by Kerry W
Put a rear-set footpeg on it for the trial duration?
Thanks for that suggestion, but a standard length lever should be fine. The extended shifter is a lot more pleasant to use, which is welcome on long rides, but the short shifter will be fine for the relatively few runs I expect to have to make with the AFR instrumentation.

Addendum: a short gear lever from a box of spares clears the pipe without problem.

Attached Files Catalina_shortgearlever.jpg
Last edited by Magnetoman; 07/23/19 5:24 am. Reason: Addendum: photo
Re: 1962 Catalina [Re: Magnetoman] #779633 07/24/19 10:46 pm
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There are several overlapping threads happening right now, with relevant information (for me) scattered between them. So, to increase the odds of me being able to find things later, I'm (re)posting some of it here along with new information.

I checked the air flow of my Catalina's filter box assembly with the borrowed Catalina head still on the flow bench. That is, I measured the total flow from the outside air, through the head with the valve opened to 0.46" (which is the valve diameter x0.25), and into the cylinder. Later, after removing the head and cylinder from the flow bench, I checked the filter assembly by itself.

A program I'm using asks for carburetor flow data at 20.4" H20 so I've converted the values to that pressure.

CFM (flow when attached to the head)
184.1 head with radiused inlet guide
165.9 bare head
150.2 head with 1-5/32" Monobloc without an inlet trumpet
145.8 with filter assembly attached but without any filter material in it
139.6 with oiled UNI BF-5 red coarse foam filter material
135.5 with original BSA filter material (of unknown amount of prior use)

CFM (flow when directly mounted to flow bench)
231.3 with oiled UNI BF-5 red coarse foam filter material
211.0 with original BSA filter material (of unknown amount of prior use)
127.1 bare 1-5/16" Monobloc (without filter)

Note that the bare Monobloc flows less than the head + Monobloc. This isn't a mistake. Basically, with a flow bench you have to be careful only to compare apples to apples, e.g. the flow of a bare Monobloc vs. a bare GP. Once you add anything to one of them you have to add it to the other to make a comparison. For example, which flows more: one carburetor spacer, two spacers, a Monobloc by itself, or a Monobloc along with two spacers?

CFM
144.3 both spacers together
141.2 both spacers plus the Monobloc
139.4 larger spacer alone
134.2 larger spacer plus the Monobloc
127.1 bare Monobloc

The above shows the Monobloc with two restrictive spacers flows 11% more than when by itself. Looked at another way, even though adding the two spacers roughly doubles the total distance the air has to travel vs. that of the carburetor alone, more air flows through the combined system than through just the carburetor alone.

Aside from the engine simulation I'm discussing in a different thread, having 25 dyno curves to study made me aware of something I hadn't appreciated before. As the factory dyno curves in the third image show, despite the smaller inlet tract and carburetor, a Catalina with 8.5:1 piston and gentler inlet cam holds its own against a Clubman and Competition, the latter with 10:1 piston, up to the maximum 6500 rpm of the Catalina's test. Only if the Competition stays above 6000 rpm does it have an advantage.

While the factory measurements could be off somewhat higher or lower, the location of the peaks in the torque curves contains important information. As can be seen, the torque of the Clubman and Competition peak at ~5500-6000 while the Catalina is somewhere below 4000. This means that up to ~6000 rpm the Catalina has an advantage. I suspect if Gold Star owners are honest, most wouldn't claim there are many times their tach needles venture north of the '60'. Since I now have Clubman overall gearing in my Catalina, I anticipate some roll-on acceleration tests to investigate this the next time there are two of us on a ride.

The h.p. required to overcome air resistance increases as velocity3. So, despite the Clubman's relatively anemic engine, somewhere beyond ~80-90 mph its wrist-killing clip-ons will come into their own because the seating position of the Catalina limits how small the rider can scrunch. However, the third figure indicates that on most roads, most of the time, in most parts of the country, a Catalina is the one to have if you want the fastest Gold Star on your block.

Attached Files FlowBench13.jpgFlowBench14.jpgDBD_Competition_Clubman_Catalina.jpgTachometer.jpg
Re: 1962 Catalina [Re: Magnetoman] #779925 07/28/19 7:07 pm
Joined: Nov 2011
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Magnetoman Online Content OP
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The photograph shows my Catalina just before making its first instrumented jetting run, which also tested my new, upgraded "instrumentation package." Inside the pipe is an insert that was in the Catalina pipe, and at the end is the Catalina's shorty silencer, so the setup reproduces the Catalina's exhaust configuration. Despite the small size of the silencer it's definitely quieter than the 'twitter' on the Competition.

What appears to be a jumbled mess of wires suspended over the handlebars is actually... well, a jumbled mess of wires. However, before cutting any wires and making a final "universal" mounting setup I needed to test everything to be sure it worked together. Unfortunately, although it works well statically, one component gives up when it shakes as much as it does at the end of the present mounting stalk. I'll address that with a Mark II mounting bracket. However, although the data logging part of the instrumentation failed, the AFR gauge didn't, so I was able to determine that the jetting appears to be OK in the lower range but the main jet needs to be smaller.

An interesting "discovery" I made today was that the Bosch knock sensor and aftermarket control unit I installed actually works. Adjusted as per instructions the LED flashed only infrequently with what I assume were false positives, but when I headed up a hill going way too slow in 4th I got the engine to rattle momentarily even with the 100 octane I had in the tank, and at the same time the LED flashed vigorously. The LED is quite bright even in the fullness of the almost-noon July desert sun.

The DocZ was especially useful since I discovered the kickstart lever doesn't clear the silencer. However, the fact that over the past several months I had fully acclimated to the Triumph shift pattern of the Competition caused me trouble more than once. The Catalina is back up on the lift for me to devise a more stable, but easily interchangeable, universal mounting platform.

p.s. the subject of holding the two BA nuts on the air filter box came up in another thread. For what it's worth, I use the lowest strength Loctite for this (purple, 222). All other things being equal, it's about 1/4 the strength of the blue.

Attached Files Catalina_AFRsetup02.jpg
Re: 1962 Catalina [Re: Magnetoman] #779946 07/28/19 11:40 pm
Joined: Oct 2006
Posts: 3,184
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Irish Swede Online Content
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WHAT are those UGLY things on the front and rear of this otherwise GORGEOUS competition bike?

OH NO! A headlight and a tail light!

And a swept-back "clubman" exhaust, too?

My 1960 "Cat" apparently had that type of exhaust on it at one time. It wore a groove across the "BSA" logo on the timing cover.
I'm still trying to find a better one.

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