Speedo washer

No idea, but at least you should have a quicker steering bike. The later models had smaller plastic front guards, but that would be pretty horrible on a 3c. I have heard tails about filling damaged pipes with sand so they don't kink and moving them with heat and pressure, but how you do that and not change the position of each end and only the middle I have no clue.
 
Just checked the angle of my forks to compare with the meassures from Vince post (thank you) my forks are 23’5degrees, and they have 1’5degrees difference with the frame head tube aprox. So it looks that the fork is “too vertical”.😣

I guess trying to correct it is a massive work that can have unexpected consequences.

I will try to find a shorter pipe!

Regards
 
michipons said:
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Miguel,
I'd first check, what the influence is, when you mount the fender bracket in the correct way. I may be wrong, but from the picture above it seems that the rear lower edge isn't as close to the tyre as on my 3c below:

51738238740_536d7dc827_b.jpg


BTW: What frame-no. is yours ..?

Cheers,
Jo
 
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michipons said:
my lower yoke shaft, has a bit of an angle with the head pipe… could it be the reason for the backwards position instead of a bent frame? I don’t see how to overhaul this as the position is governed by three straight bars…

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This does not look right, the gap front and rear should be an equal same thing left to right I believe this is the problem, could be as simple as the bearing not being seated correctly in the frame headstock. Or do you have a bent steering stem in relation to the lower fork yoke, I experienced exactly that after a crash I was able to source a replacement from Wolfgang, HTH, nice restoration you have done there.
 
The only time I managed to clout the front mudguard with the exhaust on my 3C was when I had to do an emergency stop from speed two up with luggage and even then it was the mudguard itself not the centre downpipe that was dented.
 
78jotadave said:
This does not look right, the gap front and rear should be an equal same thing left to right I believe this is the problem, could be as simple as the bearing not being seated correctly in the frame headstock. Or do you have a bent steering stem in relation to the lower fork yoke, I experienced exactly that after a crash I was able to source a replacement from Wolfgang, HTH, nice restoration you have done there.
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Yes, i thought about that… but if that would be the case I could not put the tubes through both yokes?! But well, after monday MOT I will re-check that.

Pf1, is not the mudguard hitting but the bracket, which is much stronger…
 
What Miguel would like to try is a centre header pipe from a later model 3CL/Jota where the centre header sits back closer to the engine,
I will try to take a photo later looking across so you know what I mean, but I will be riding
Read it and weep :) :) :) :) :) :) :) :) :)
 
@Piet is basically right, frame is bent, and I have to fix it. I will. Promised😇. I even thought how I will do it. But until I have time for that, I would like to enjoy the bike for a while.

Wolfang told me a Wirth fork spring will help, if I can find one of those center headers, even better.

And this thread started with a speedo washer…🤣🤣, well, good news is that the washer is there🤣🤣.
 
I think I would spend a bit more time looking at that bottom yoke & stem...... You may have a mix of parts that have been bent or fixed by a previous owner.
I had a bend in the stem on an older bike that really shouldnt have allowed assembly of the fork tubes but it all went together.
 
After careful inspection of the lower yoke, the stem angle is adequate. Where the bearing rests, the lower yoke has a surface that is uneven, higher in the from lower in the back, to allow the forks to have the offset angle, so basically the stem has an angle with the lower yoke. So the angle that is visible between the yoke surface and the head tube is correct. I will try to take a photo where this is visible.

However, Wolfang told me that Ceriani forks came with different offset angles, 1’5 is correct for the 3C. For example, the ceriani fork of my SF3 has no offset angle, and the bearing rests totally flat with the lower yoke.

Unfortunately, and as usual here, Piet is correct, all leads me to the fact that the frame is slightly bent. Will fix it some day. For the time will try to avoid the contact with a stiffer fork spring. I bought the one from Wirth, it cannot hurt, and my springs must be worn after 50 years service… the impact happen when the fork compresses 110mm, if I can reduce it to 100mm that would solve the issue.
 
Yep, I agree. Enjoy it as it is and bit the bullet when the time is right. As long as it's handing and riding well it's all good. When you do it add the frame strengthening anti-cracking braces at the same time. As I said its a lovely looking bike. Enjoy
 
michipons said:
However, Wolfang told me that Ceriani forks came with different offset angles, 1’5 is correct for the 3C. For example, the ceriani fork of my SF3 has no offset angle, and the bearing rests totally flat with the lower yoke.
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SF3 came standard with the same kicked back Ceriani triple clamps as SF2. SFC had parallel.
 
I respectfully suggest that, when you get a chance to strip the bike down to the frame, you compare your frame dimensions and angles to the diagram 3c Wayne supplied, rather than take a remote diagnosis of a "bent frame".
As above #32, Patrick reported exhaust strikes prior to a front fork overhaul on his 120° Jota, which the overhaul completely cured.
Your bike, your call.
 
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The Sock said:
I respectfully suggest that, when you get a chance to strip the bike down to the frame, you compare your frame dimensions and angles to the diagram Vince supplied, rather than take a remote diagnosis of a "bent frame".
As above #32, Patrick reported exhaust strikes prior to a front fork overhaul on his 120° Jota, which the overhaul completely cured.
Your bike, your call.
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Sure, if I do something like that I would check all dimensions. However, I re-meassured the angle assuring a flat frame as vince sugested, the fork angle was 23/24 degrees, which is 3/4 degrees difference (backwards)

I can’t see how overhauling the fork cou solve the issue, actually it is totally overhauled, except for the springs that I will swap next week.

I already checked the top tube, made a video and sent it to a very respected Laverdist, he told me. “Thats bent brother”😑
 
I didnt supply the frame diagram, that was Wayne out of the USA and a handy diagram it is. I think you need to refer to other frame members as using anything while it's on its wheels won't help. It needs a datum as a starting point to check frame angle and alignment. Best with some kind of rod extending through the steering head and swingarm pivot. I am a big fan of Motoliners, jigs with hydronic rams for frame alining, not so common around these days. You need to alien from the swingarm pivot centre.
 
Vince said:
I didnt supply the frame diagram, that was Wayne out of the USA and a handy diagram it is. I think you need to refer to other frame members as using anything while it's on its wheels won't help. It needs a datum as a starting point to check frame angle and alignment. Best with some kind of rod extending through the steering head and swingarm pivot. I am a big fan of Motoliners, jigs with hydronic rams for frame alining, not so common around these days. You need to alien from the swingarm pivot centre.
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When the time comes, I will ask for advice!👍🏻💪🏻
 
Vince said:
I didnt supply the frame diagram, that was Wayne out of the USA and a handy diagram it is. I think you need to refer to other frame members as using anything while it's on its wheels won't help. It needs a datum as a starting point to check frame angle and alignment. Best with some kind of rod extending through the steering head and swingarm pivot. I am a big fan of Motoliners, jigs with hydronic rams for frame alining, not so common around these days. You need to alien from the swingarm pivot centre.
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I rode mine for years with the bent frame using a fender from a Suzuki without a brace. I finally bit the bullet one winter and took it to Comutrack near Boston.

https://www.computrackboston.com/Motorcycle-Frame-Straightening-s/3003.htm

The process was pretty evasive, and he worked with the diagram I provided. I dropped it off sans seat, tank, headlight, clocks, battery, wiring harness back to battery, exhaust system and carbs. One week and $800 later it was all good. Required paint touch-up afterwards.

Happy when it was done.
 
3C-Wayne said:
I rode mine for years with the bent frame using a fender from a Suzuki without a brace. I finally bit the bullet one winter and took it to Comutrack near Boston.

https://www.computrackboston.com/Motorcycle-Frame-Straightening-s/3003.htm

The process was pretty evasive, and he worked with the diagram I provided. I dropped it off sans seat, tank, headlight, clocks, battery, wiring harness back to battery, exhaust system and carbs. One week and $800 later it was all good. Required paint touch-up afterwards.

Happy when it was done.
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Ok, thanks. I can’t go to boston but i will find somebody here wit probably more basic tools but will for sure work. I guess that some car workshops do it with much more complexity.
I would bring it there totally naked.
Thank you for the diagram, is going to be extremely helpful. This community is really cool, thxs to all.
Miguel
 
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