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'79 Fork stanchion size? #328139
08/14/10 12:52 pm
08/14/10 12:52 pm
Joined: Aug 2010
Posts: 170
Maryland
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Al J Offline OP
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Folks:
New on board here, the forum looks like a wealth of information. I have a '66 TR6C chopper with a bonnie dual-carb head. The front end is toast and the stanchions don't look worth rebuilding. I found and bought a whole front end set up for a '79 bonnie on eBay. I'm picking it up next week.
My current triple trees (very nice condition with tapered bearings) hold the 35 mm forks. I can't find out what size forks will come with the '79 disc-brake set.
It would be nice just to slip on the new forks and use my existing conical wheel for the rest of this season.
If that won't work, will my existing neck bearings work with this triple tree? I have slightly higher than stock bars, so I would need a longer hydraulic brake line, but a vintage shop near me makes those to order, so no issue there.
You can see pictures of my project here:
http://rides.webshots.com/album/551926627CJCEId?start=84

The existing front end looks like this:


'66 TR6C Chopper
'02 Bonneville America
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Re: '79 Fork stanchion size? [Re: Al J] #328145
08/14/10 1:48 pm
08/14/10 1:48 pm
Joined: Jul 2009
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Vic. Australia
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Pete R - R.I.P. Offline
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Looks like you currently have '71 or '72 forks.The staunchions are a taper-fit into the top yoke.
Disc brake staunchions don't have a taper at the top;they're parallel and held by pinch bolts at the top yoke.Diameter is the same as you have now.

You may be able to use your lower yoke and bearings.The top yoke will have to be the pinch-bolt type to suit the new staunchions.

Re: '79 Fork stanchion size? [Re: Pete R - R.I.P.] #328162
08/14/10 4:02 pm
08/14/10 4:02 pm
Joined: Aug 2010
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Al J Offline OP
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Hey, thanks. I forgot about the taper aspect. He's giving me a new triple tree set, but it would be nice to continue to use part of that new headset.


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #328182
08/14/10 6:33 pm
08/14/10 6:33 pm
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Posts: 3,825
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DMadigan Offline
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The stanchion spacing (width) is 7-5/8" on the disc brake models, narrower (6-7/8"?) on the drum brake. You will not be able to mix and match triple clamps and stanchions. The outer diameters are the same though.
"slightly higher then stock bars"?

Re: '79 Fork stanchion size? [Re: Al J] #328185
08/14/10 6:45 pm
08/14/10 6:45 pm
Joined: Jun 2002
Posts: 10,186
Scotland
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Stuart Offline
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Hi Al,

Originally Posted By: Al J
My current triple trees (very nice condition with tapered bearings) hold the 35 mm forks. I can't find out what size forks will come with the '79 disc-brake set.
It would be nice just to slip on the new forks and use my existing conical wheel for the rest of this season.

Hmmm ... goin' to be a bit more to it than that ...

As Pete says, the '79 (disc-brake) stanchions are the same diameter (not 35mm but 1-5/16"; you have to open out Triumph yokes/triple trees to take Jap 35mm stanchions) but do not have a taper into the top yoke.

And therein will lie your major problem. frown As Pete correctly identifies, your bike currently has '71 or '72 forks (the only seasons Triumph and BSA used the conical hub front brake). More particularly, as they have taper-roller steering bearings, they're off a 650 or 750 twin - taper rollers were fitted to the oif (oil-in-frame) - but it means that something major has been done to make 'em fit the '66 frame. Pre-oif (aka 'dry') frames had cup-'n'-cone head bearings and a longer steering stem; the easier and more-usual way to fit '71-on forks (usually '73-on disc brake rather than conical hub) to a pre-'71 frame is to use the yokes/triple trees off a Triumph or BSA triple, which never went oif.

Unfortunately, there isn't any bolt-on way of using disc-brake (no taper top) stanchions with conical-hub yokes/triple trees - at the same time as Triumph went to parallel-top stanchions, they also fitted the disc brake and substantially increased the distance between the fork legs. So the conical hub brake won't fit between legs spaced by disc-brake yokes/triple trees without a special longer axle.

Then '79 yokes/triple trees are different to pre-'79 yokes/triple trees; the later ones are essentially T160 but with the oif's shorter steering stem, so the top one has cast-in mountings for the clocks and the bottom one has the steering lock (so that's in a different place on the frame too).

Fwiw, unless you plan to use more of the components from the '79 forks, I'd forget 'em for just the stanchions - to get just them to fit, you're going to have to a lot of machining to end up with a lot of non-standard parts.

Hth.

Regards,

Re: '79 Fork stanchion size? [Re: Stuart] #328241
08/15/10 4:02 am
08/15/10 4:02 am
Joined: Aug 2010
Posts: 170
Maryland
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Al J Offline OP
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Thanks fellows. I didn't mention I have the whole '79 front end:
forks, triple trees (buyer offers several options), wheel, disc, etc. Here's the listing for what I bought:
http://cgi.eBay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=160463298984&ssPageName=ADME:X:AAQ:MOTORS:1123
The seller says it will fit any non-oif frame neck. I'm hoping that is the case.
I'm have a modern Bonneville America as well and really rely on that front brake. My connical wheel/brake just doesn't grab like my disc. I'm hoping even though it is a '79, it will be a braking improvement.
My plan is to fit up this front end, than sell off my old stuff to recoup a little of my costs.


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #328242
08/15/10 4:05 am
08/15/10 4:05 am
Joined: Aug 2010
Posts: 170
Maryland
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Al J Offline OP
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Al J  Offline OP
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Btw, these are the bars on the bike now. They have about an 8" rise and are on 4" offset dogbone risers. I have the risers flipped around, so the they don't get the full 4" higher reach.


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #328403
08/16/10 11:22 am
08/16/10 11:22 am
Joined: Aug 2010
Posts: 170
Maryland
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Al J Offline OP
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Guys, I really appreciate the advice and sticking with me on this, I'm still just a little confused. Here's what I surmise:
- the disc brake front end triple trees are completely that my current setup.
- They are wider and not tapered,requiring a pinch-bolt.

So, I right now I believe this entire '79 front end can be used if I get the correct headset bearings.

The seller offers me two choices on the triple trees, the '79 set of early set (73-78). For use on my '66 frame, is there a more preferable choice?

I'm picking these up on Wednesday, is there any reason why they wouldn't fit and I should pass?


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #328417
08/16/10 1:22 pm
08/16/10 1:22 pm
Joined: Jul 2009
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Vic. Australia
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Pete R - R.I.P. Offline
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Posts: 3,549
Vic. Australia
I'd buy it,and I'd make it fit.I'd take the '79 yokes,because that gives you more options with gauge mounting.

By now,you've probably measured the staunchion centre distance and found it 6-7/8".
Disc brake centre distance is definitely 7-5/8".

The main problem,according to Stuart,is the length of the steering stem may be too short to fit your frame.A T160 lower yoke would have a longer steering stem,and that would fit.

The best thing you can do is to take out your present lower yoke and compare it to the new one.The new one will most likely have a shorter steering stem.The bearing size will be the same.

It appears to me that the steering stems are screwed into the lower yoke,but may not be easily removed.They may have silver solder sweated into the thread.On the 250 Triumph with conical hub drum brake and aluminium fork yokes,the steering stem is definitely screwed in.

I hope this gives you a clue on what you are up against.

Answer to your original question:Staunchion diameter for these
forks is 1.3605"-1.3616",reduced to 1.3537"-1.355" near the top.
Earlier (dry frame) staunchions were 1.3025"-1.303" .

Re: '79 Fork stanchion size? [Re: Pete R - R.I.P.] #328421
08/16/10 1:42 pm
08/16/10 1:42 pm
Joined: Aug 2010
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Al J Offline OP
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Maryland
Thanks again Pete. I'll pull my front end and take along that triple tree/stem set to compare against. I hadn't considered the stem height might be different.
The '79 set is still at the sellers place in New Jersey(3.5 hr drive). The seller does Triumph repairs out of his garage and seemed like he might be helpful in putting this puzzle together.

On a forum note, I'm not getting email notification on thread replies. I've been checking "Add this thread..." on teh Post options box. Anything I can do in my "My Stuff" to have auto-subscribe on topic replies?


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Pete R - R.I.P.] #328452
08/16/10 6:42 pm
08/16/10 6:42 pm
Joined: Jun 2002
Posts: 10,186
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Stuart Offline
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Hi Pete,

A few minor corrections:-

Originally Posted By: Pete R
you've probably measured the staunchion centre distance and found it 6-7/8".

Conical hub is 6-3/4", same as '69 and '70. As you and Dave said, disc-brake centre-to-centre is 7-5/8"

Originally Posted By: Pete R
The main problem,according to Stuart,is the length of the steering stem may be too short to fit your frame.

I was waiting to see what happened when Al got his '79 forks. He says in his original post that the steering bearings are already taper-rollers. As '71 650 oif twins were the first to get both taper-rollers and the comical hub, this suggests Al's bike's steering head has been converted already.

Originally Posted By: Pete R
A T160 lower yoke would have a longer steering stem,and that would fit.

I wouldn't bank on it fitting. The T160 is peculiar in that is has a 'dry' frame, and the corresponsing steering head casting, but machined for taper-rollers, so the steering stem's peculiar. Anyway, as T160's can't use anything but T160 yokes, I'd rather people didn't bash 'em about for specials and make it even more difficult to keep T160's on the road. wink

I'm actually expecting the '79 yokes to fit Al's bike but, as I say, was keeping schtum 'til he posted something/anything. whistle

Hth.

Regards,

Re: '79 Fork stanchion size? [Re: Stuart] #328512
08/16/10 11:41 pm
08/16/10 11:41 pm
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Maryland
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Al J Offline OP
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The set was advertised to fit "non-OIF Triumphs".
Should I pass on this and just rebuild my existing set? (I don't want to wreck anything historic either on this just yard-dog bobber).
I'm actually having one heck of a time at the present getting my triple trees off, will post that as well.


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #328636
08/17/10 5:22 pm
08/17/10 5:22 pm
Joined: Jun 2002
Posts: 10,186
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Stuart Offline
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Hi Al,

I didn't really want to possibly confuse this thread with the following but, as it's becoming more confused anyway ...

From your first post:-
Originally Posted By: Al J
I found and bought a whole front end set up for a '79 bonnie on ebay.

From your last post:-
Originally Posted By: Al J
The set was advertised to fit "non-OIF Triumphs".

With respect, someone is confused here, whether it's the seller, you or both of you. The forks cannot be both because, in 1979, (what was left of) Triumph only made oif.

'71 to '74, Triumph fitted basically the same forks to both 650/750 twins (oil-in-frame) and triples (dry-frame); if you ignore the springs'-'n'-dampers differences between twins and triples, the only other difference was the bottom yoke. Of this, only the steering stem is actually different, but they're pretty-well attached to the bottom yoke itself. wink

Because the T150 (dry) frame always used exactly the same steering head dimensions and frame-to-forks bits as pre-'71 twin (dry) frames, to fit conical hub or disc forks to a pre-'71 twin or triple is essentially a bolt-on job if you use the relevant yokes from a triple. However, because your bike's steering head has been modified already for taper-roller bearings, afaict you won't be able to use a triple's bottom yoke, because they use cup-'n'-cone bearings. I suspect that, when you told the seller your bike's frame was '66, he immediately thought 'dry frame' and included those yokes.

Originally Posted By: Al J
I'll pull my front end and take along that triple tree/stem set to compare against.

Sounds like a plan. bigt

Originally Posted By: Al J
Should I pass on this and just rebuild my existing set?

We-el-ll, if you want to go to a disc front brake, a complete set of forks off a '79 is as good a way to go as any, especially if the '79 steering stem fits your bike's steering head.

Originally Posted By: Al J
(I don't want to wreck anything historic either on this just yard-dog bobber).

I was sort-of joking. wink I'd be surprised if the seller is supplying a T160 bottom yoke and I'd be quite surprised if a T160 steering stem actually fitted, but if it does without modification ... It's the irreversible mods. we don't want ... wink

Hth.

Regards,

Re: '79 Fork stanchion size? [Re: Stuart] #328679
08/17/10 10:42 pm
08/17/10 10:42 pm
Joined: Aug 2010
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Maryland
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Al J Offline OP
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Thanks Hth, I'm getting an education. I'll pick them up tomorrow in person and compare the yoke options. I spoke to the guy who put the current triple tree and bearing on the bike and he thinks the '79 front end should bolt right up. I'll report back!


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #328799
08/18/10 6:19 pm
08/18/10 6:19 pm
Joined: Jun 2002
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Stuart Offline
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Hi Al,

Originally Posted By: Al J
Thanks Hth,

confused Hth = Hope This/That Helps.

Hth.

Regards,

Re: '79 Fork stanchion size? [Re: Stuart] #328800
08/18/10 6:26 pm
08/18/10 6:26 pm
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Posts: 1,526
Farmington,Connecticut,USA
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Hi Stuart,
When i first met Tridentman, i logged him into my mobile phone list as "HTH Tridentman"

!

grin


1978 Bonneville T140V PX
Re: '79 Fork stanchion size? [Re: JBMorris] #328812
08/18/10 7:03 pm
08/18/10 7:03 pm
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Posts: 10,205
Boston, Massachusetts
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John Healy Offline

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And he is very helpful!


Re: '79 Fork stanchion size? [Re: John Healy] #328818
08/18/10 7:19 pm
08/18/10 7:19 pm
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New Jersey USA
Tridentman Offline

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Thanks guys.
HTH!!!!!!!!

Re: '79 Fork stanchion size? [Re: Tridentman] #328875
08/19/10 2:04 am
08/19/10 2:04 am
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Al J Offline OP
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Well, I picked up the '79 front end today from a small shop up near Trenton NJ and it feels like a homerun. It is almost too nice to put on my crusty chopper. The triple tree matches up to my existing set perfectly and should slide right on. The wheel is beautiful, barely looks run. The guy had some beautiful bikes outside and seems to do some outstanding work. The bike under the cover is a triple cafe racer. There were cool bikes all over, but I didn't want to be too nosey since I just met the dude. I'll definitely use him for future parts, etc. He said he's been at this location for over 25 years.

One issue is the hand control. It works fine (per the seller) and he gave me another set so I can have the mounting piece (empty hand control unit). He said a lot of guys put on smaller fluid reservoirs, off dirt bikes, etc. Does anyone have a suggestion on an economical, smaller replacement? I'm betting there are a lot of dirt bike pieces on eBay, but I'm not sure what has to fit up to the Triumph caliper. I have a local vintage shop nearby that can make me a new brake line and eliminate the brake switch junction.

He gave me the brake disc, but it's pretty rusty. I'll drop it off at my local shop to see if they can surface it. Anyone know what a new disc runs?

Included are the p-clamp risers, a nearly new fender and brace. I'll probably sell off those things, but might keep the fender brace to stiffen the front end. The fork legs look terrific and should polish up beautifully this winter.







Btw thanks for the tips Stuart, formerly known has HTH!


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #328891
08/19/10 3:42 am
08/19/10 3:42 am
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KY, USA
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Crap, looks like I got to the post too late.

FWIW, I prefer Conicals or earlier TLS front brakes to the factory disk setup.

1. They can be made to stop as well as or better than factory disk if setup properly.
2. You don't have that big honkin master cylinder hangin' off your bars for a much cleaner look, especially on a bobber/chopper!
3. So whatayawant for the take-off Front end and wheel?

Last edited by RyanF; 08/19/10 3:44 am.

1950 BSA A10 Chopper 1951 BSA Golden Flash
1960 Triumph 5T
1962 BSA A65 Royal Star
1968 BSA A65 Bobber - In Progress
1969 Triumph T120 Bobber "The Rabbit"
1972 Triumph T120RV
Re: '79 Fork stanchion size? [Re: RyanF] #328940
08/19/10 12:42 pm
08/19/10 12:42 pm
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Al J Offline OP
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Yes, I'm mulling over the switch to the disc. My buddy says the same thing about the conical brake, he thinks its not set right. I'm waiting for my new tire and will decide what to do shortly. If I go with the disc brake, I'll put these things up here first. Looking around on eBay it looks like prices are in the ranges of?
- conical wheel ($100), rim is in poor shape
- 60's triple tree set, powdercoated ($100)
- OEM p-clamp risers ($25)
- '79 front fender (looks new) ($75-$100ish?)
Originally Posted By: RyanF
Crap, looks like I got to the post too late.

FWIW, I prefer Conicals or earlier TLS front brakes to the factory disk setup.

1. They can be made to stop as well as or better than factory disk if setup properly.
2. You don't have that big honkin master cylinder hangin' off your bars for a much cleaner look, especially on a bobber/chopper!
3. So whatayawant for the take-off Front end and wheel?


'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #329087
08/20/10 8:34 am
08/20/10 8:34 am
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Stuart Offline
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Hi Al,

Originally Posted By: Al J
Does anyone have a suggestion on an economical, smaller replacement?

The Lockheed single-disc master cylinder is 5/8" i.d. For some years, Dave Madigan ("DMadigan" on here) has offered a service that sleeves it down to 1/2" and people I know who have the smaller i.d. master cylinder say it makes for a nice brake.

That said, I appreciate it's still the original master cylinder and mounting, and you might not want that; however, it means you can look for a dirt-bike master cylinder around 1/2" i.d. Or you could consider a Jap bike master cylinder. I know Honda used (still uses?) 14mm (9/16") i.d. and many of its cylinders clamp direct to the 'bars independent of any switch clusters. That you're having a braided hose made up means the master cylinder end fitting can be whatever's needed (the standard Lockheed one is 3/8"UNF if you were wondering wink ).

Originally Posted By: Al J
a new brake line and eliminate the brake switch junction.

I wouldn't eliminate the hydraulic brake switch entirely. The alternative, that Triumph used from '73 to '78, is a piece of plastic with two wires inside the master cylinder mounting, pressed by a tiny screw in the end of the brake lever. Sound Heath Robinson? It is. frown

My T100 has a single disc. I used the brass 'T' turned on its side:-

. the bottom of what's then the vertical is screwed on to the top end of the pipe from the caliper through the bottom yoke eyebolt;

. the switch is screwed into the top of what's then the vertical, which places it just under, behind and to the left of the headlight shell;

. the hose from the master cylinder is screwed into what's then the horizontal of the 'T'.

Alternatively, if you're having a banjo at the master-cylinder end of the hose, Goodridge make banjo bolts that incorporate a hydraulic switch.

Originally Posted By: Al J
He gave me the brake disc, but it's pretty rusty. I'll drop it off at my local shop to see if they can surface it.

Hopefully, this means all the chrome's come off - if not, the shop needs to grind off any remaining. Fully-chromed or not chromed at all, these discs are good in the wet; part-chromed, they're carp.

However, before it's surfaced properly, I'd advise just cleaning off the rust and painting it. If you paint it after, you'll have to faff around masking the braking area; if you do it before, the surfacing process will remove any paint from the braking area. bigt

Fi, original discs, and replacements for many years, had a 45-degree chamfer at the two corners (inner and outer) of the outer edge of the disc. These are the wear indicators - if they aren't present, the disc has reached its minimum thickness. However, just to confuse things, replacement discs made certainly in the last few years don't have the chamfers from new. frown I've some original discs still with the wear indicators so, if you need to know the mininmum thickness ...

Originally Posted By: Al J
might keep the fender brace to stiffen the front end.

If the fender mounts to the brace with three bolts - two between the legs and one ahead - that was first used on the T160. It's good at keeping the sliders going up and down together but, with a single disc, not much cop at stopping the sliders twisting under braking, but then the earlier 'hoops over the fender' braces from the drum-brake era weren't good either. frown If you find you like the disc brake better than a drum (and a good disc is wa-a-ay better than either drum, but particularly the 'comical'), you could look around for one of the after-market braces.

Originally Posted By: RyanF
Conicals or earlier TLS front brakes to the factory disk setup.

1. They can be made to stop as well as or better than factory disk if setup properly.

As we're talking about forty-odd-year-old brakes, you have to be careful that you're comparing like with like. The factory manuals don't contain all the servicing advice, simply because they weren't written with forty-odd years of neglect and d.p.o. in mind. If I serviced and upgraded all three brakes according to, say, the best advice on these Boards and the single disc didn't perform noticeably better than either drum, I'd take up something like tiddlywinks.

The single disc has at least three other advantages over either drum:-

a. If your rides consist of roads with lots of corners that require braking, especially downhill as well, either drum will start to fade long before a disc will, if the latter ever does (you can persuade it to fade on a T160 but we're talking about a bike 100lbs heavier than a twin).

b. To keep them working at optimum, drums require constant fiddling and fettling; in contrast, discs simply work and carry on working.

c. If a single disc isn't enough, you can simply bolt on another one, as the Co-op started to do just before it went bust. Then there are after-market 12" and/or floating discs; the alternative exotic drums are far more expensive and heavier but still can't match the performance of discs.

Originally Posted By: RyanF
2. You don't have that big honkin master cylinder

I've seen numerous bobbers/choppers with disc brakes and 'clean' handlebars; there are any number of small and/or remote master cylinders; just depends on ingenuity and/or your credit-card limit. wink

Hth.

Regards,

P.S. With standard Lockheed discs, be aware there are two slightly different diameters - 10" (254mm, made before about 1980) and 250mm (made after 1980). The calipers are the same so there are two different pads because, if you use pads intended for a 10" disc with a 250mm disc, you end up with a ridge of pad material that isn't worn away.

Last edited by Stuart; 08/21/10 5:25 am. Reason: Disc diameters
Re: '79 Fork stanchion size? [Re: Stuart] #329302
08/21/10 5:10 pm
08/21/10 5:10 pm
Joined: Aug 2010
Posts: 170
Maryland
A
Al J Offline OP
BritBike Forum member
Al J  Offline OP
BritBike Forum member
A

Joined: Aug 2010
Posts: 170
Maryland
'79 Front end is installed. It went on pretty easy, my tapered bearings slipped right on, after I removed the thick coating of paint on the neck stem. I had to modify my headlight mount just a tad for the wider mount points. I also installed a new set of V-twin rubbers on my risers, the old ones were toast.

I ordered a "slimline lightweight master cylinder" for an XS650 from Mikes. $75 delivered, that fit my slimline budget...
http://www.mikesxs.net/products-71.html#products

My tire/tube/strip will be here on Monday.

A local shop can make me a hydraulic brake line to match the caliper and master cylinder.

I probably should lower it a bit, but than can wait till winter. I curious to see how it rides with the new forks.


Last edited by Al J; 08/21/10 5:11 pm.

'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #329808
08/24/10 9:28 pm
08/24/10 9:28 pm
Joined: Aug 2010
Posts: 170
Maryland
A
Al J Offline OP
BritBike Forum member
Al J  Offline OP
BritBike Forum member
A

Joined: Aug 2010
Posts: 170
Maryland
New Duro Tire came today, got it mounted and installed with the '79 front end. Took if for a quick spin around the neighborhood. Wow, rides pretty nice.

New master cylinder is supposed to be here Thursday, hopefully by Saturday I'll have it mounted and working. I guess you get used to it, but boy is it strange riding without a front brake.

I had some spare time on Saturday and couldn't resist polishing the fork legs. No prep, just hit the wheel with some white rouge. That really doesn't fit the character for the rest of the bike, so I'll probably scotchbrite them at some point. Oh well, one day with a little wet sandpaper they would really gleam

My buddy said don't bother machining the front disc rotor, he has a few good spares and I can use one.



'66 TR6C Chopper
'02 Bonneville America
Re: '79 Fork stanchion size? [Re: Al J] #330267
08/27/10 10:15 pm
08/27/10 10:15 pm
Joined: Aug 2010
Posts: 170
Maryland
A
Al J Offline OP
BritBike Forum member
Al J  Offline OP
BritBike Forum member
A

Joined: Aug 2010
Posts: 170
Maryland
Well, my project came to a screeching halt.

I ordered the Goodridge line and fittings from my local shop. My new master cylinder came with a banjo bolt and the guy asked me if I had the banjo bolt for the caliper. I wasn't sure as the OEM line fittings were back on my bench (only brought the caliper).

I got home and found the OEM setup was a hard line into the caliper. There was a banjo bolt into the OEM master cylinder and it is threaded the same as the caliper. But, it is too long and has an internal ridge as seen in this photo. The OEM hardline is also below



You can see how the OEM banjo bolt sticks out of the caliper too far to work in this photo:


The Goodridge lines work with this type of fitting


The shop guy tried a number of Goodrige banjo bolts, but none of the thead pitches worked. Is there anyway this is a British thread fitting? Doesn't seem possible coming off a '79, but he could not get a read on a metric pitch.

He suggested getting either
A - shorter banjo bolt but not sure how or where to find such a thing. The parts manual for a '79 would only show OEM stuff
B- have a machine shop cut down that banjo bolt and remove the ridge near the head.

Any thoughts or advice on this dilemma?


'66 TR6C Chopper
'02 Bonneville America
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