Transposing Mk 111 disc to timing side rear

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trident sam

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After years of owning Mk 111 Commandos I thought I'd switch the fork legs round to have the front caliper behind the timing side fork leg. I'd read and heard that when the factory had fitted it in this position (as in all other disc bikes) the bike pulled over to one side, and didn't really believe it. Anyway, spent an afternoon switching it all round, turning tyre, making new brake line etc etc. Guess what - The bloody bike pulls over- it's very disconcerting and now I have to switch it all back over.
As there's no fool like an old fool, I'll still try it on my other Mk 111, after all, I have the brake line etc allready made up. :?
Will report back once I've done it.
sam
 
This has been discussed before, but I've never found a reasonable explanation why? If it is because there is only one brake then it should happen on either side. My opinion, and just to be clear, this is my opinion, not an expert opinion, or an opinion based in facts that I can post to insure that people will not rip me a new one, is that the forks are twisting. This is why a properly installed fork brace makes sense. Notice that I said "properly installed". Properly installed means a fork brace that still allows the forks to function as intended. No stiction or binding. I know I will be told this is impossible, but I seem to have been able to accomplish this with my MKIII. I also have moved the brakes to the right, but have not been able to test them yet.
 
That's odd. Both my Commandos have a single disc with caliper behind the leg. They both brake in a straight line. They did so with the original Lockhead caliper & disc & also with the four pot calipers & 13" discs now fitted. The mk 2a front end geometry is the same as mk 3 as far as I am aware. Maybe someone will chime in with the reason.
Martyn.
 
I turned the brakes round to get the brake pad orientation correct , Brembo 4 pot caliper, I found out on this site the small pads should act on the disc first . When the brake was on the left the larger pads were acting first, even though it seemed to me to work just fine.
after reading Matt from CNW post that the caliper is ok either before or behind the fork leg I'm still a bit confused. Ludwig and Ron L had stated it's a bad idea to have the larger pads acting before the smaller ones. :? :? :?
sam
 
trident sam said:
I turned the brakes round to get the brake pad orientation correct , Brembo 4 pot caliper, I found out on this site the small pads should act on the disc first . When the brake was on the left the larger pads were acting first, even though it seemed to me to work just fine.
after reading Matt from CNW post that the caliper is ok either before or behind the fork leg I'm still a bit confused. Ludwig and Ron L had stated it's a bad idea to have the larger pads acting before the smaller ones. :? :? :?
sam
Click to expand...

I read what Matt wrote in that other thread and wondered why he said that the caliper could be mounted on either side because the piston size is different in order to get consistent pad wear and the caliper should be oriented correctly. I guess Matt is wrong too. So if we are stupid...what's that say?

So you are having a problem with the Brembo on the right side? Have you checked all of the other culprits? Tires, iso's, etc.?

You aren't anymore confused than I am...and many other's given the search info I've found. Is it the weight? Offset? Tires? Something else? Doesn't make any sense. Even Norton couldn't explain it.
 
Dennis,

I don't think we are thought of as stupid (hope not anyway) but on my bike I changed nothing apart from the caliper mounting side , wheel/tyre direction, and it turned from braking properly to pulling over. The bike still handles great, just not when I use the brake :shock:
sam
 
I switched my MK3 over in order to make use of the Madass six pot 320mm brake. There is no problem with pulling, strange that the stock item does this when reversed.

Glen
 
trident sam said:
Dennis,

I don't think we are thought of as stupid (hope not anyway) but on my bike I changed nothing apart from the caliper mounting side , wheel/tyre direction, and it turned from braking properly to pulling over. The bike still handles great, just not when I use the brake :shock:
sam
Click to expand...

I can't figure out if the pulling referred to in the Norton technical specs is during braking or when riding...some talk about releasing the bars while moving and the bike does not steer straight. Some discussion about weight of caliper and MC on same side. Further discussions about steering head shifting due to weight. Wheel offset and tire type and wear are also brought up. My assumption is/was what you are referring to, that the bike pulls to one side during braking. This is why I suggested fork twist earlier...I can't figure out why it would be different with the caliper on one side or the other though. Maybe there is more force on the fork with the caliper behind rather than in front of the slider.

But then what Matt from CNW says in the thread link I posted says it makes no difference so honestly I don't have a clue.
 
I've been riding a variety of commandos since 1988 and this is the first time I ever heard a claim that it is the BRAKE that pulls.
Where have I been...
For the last 24 years I had heard it was supposed to be....... in a hands off roll that the bike veered to the right????
 
Didn't NVT say that having two discs on one side caused it to pull ? They said it at the same time as they offered the T160 Trident with just that layout though...

The first thing that I'd check is rim offset on the front wheel. It could be that an off-centre rim was helping to correct a problem further back but is now making it worse with the wheel turned round.
 
dynodave said:
I've been riding a variety of commandos since 1988 and this is the first time I ever heard a claim that it is the BRAKE that pulls.
Where have I been...
For the last 24 years I had heard it was supposed to be....... in a hands off roll that the bike veered to the right????
Click to expand...

Yes this is what most of the information says...still not able to understand why...
 
79x100 said:
Didn't NVT say that having two discs on one side caused it to pull ? They said it at the same time as they offered the T160 Trident with just that layout though...
Click to expand...

Perhaps I've misunderstood, but a T160 had its standard front disc on the left side, and rear disc on the right? :?

Transposing Mk 111 disc to timing side rear
 
79x100 said:
Didn't NVT say that having two discs on one side caused it to pull ? They said it at the same time as they offered the T160 Trident with just that layout though...

The first thing that I'd check is rim offset on the front wheel. It could be that an off-centre rim was helping to correct a problem further back but is now making it worse with the wheel turned round.
Click to expand...



T160 discs are on opposite sides, front drive side, rear timing side.

Far as I can tell the front rim is bang in the centre. I'm thinking it's maybe what Dennis says with the forks being twisted, but I assembled it all with a lot of care. Will just carry on trying I guess.
sam
 
79x100 said:
Didn't NVT say that having two discs on one side caused it to pull ?
Click to expand...

This is interesting, I tried to find something on this on the web, but nothing. I went in the garage and looked at my Kawasaki Vulcan and Honda Aero the only bikes I have with single front brakes...front is on the left and rear is on the right...
 
L.A.B. said:
79x100 said:
Didn't NVT say that having two discs on one side caused it to pull ? They said it at the same time as they offered the T160 Trident with just that layout though...
Click to expand...

Perhaps I've misunderstood, but a T160 had its standard front disc on the left side, and rear disc on the right? :?

Transposing Mk 111 disc to timing side rear
Click to expand...

Whoops. Failing memory and failure to check facts. I was so certain that was how I remembered it. Was there perhaps something in the press at the time which said (or implied to my teenage mind) that Nortons put the caliper in front to improve the steering or something ? I recall thinking that Tridents were different.
 
dennisgb said:
I found this thread that might help explain things:

disc-brake-from-left-right-side-t5611.html
Click to expand...

mitchp has made a point. With the caliper on the rhs, it is behind the pivot point of the front wheel where it touches the ground, and also under the steering axis, so its weight will naturally tend to pull the steering round to the right.
With the caliper in the rhs, it is more over the pivot point of the tyre where it touches the ground, and maybe less likely to turn the wheel to the left in this case. I would have thought more weight on one side would tend to turn the wheel slightly to that side in theory. In my case with my 74 850, I have never noticed a "pulling to one side" ever so have never thought about it before.
Cars have 2 wheels in front, which have balancing forces, to keep things going in the right direction.
 
With all the heat Norton gets for crappy "what were they thinking" design flaws, just maybe they engineered the caliper locations on two caliper bikes because it works well that way. If both calipers had been located on the same side from the get-go and the bike pulled to the right, we'd all be saying "what were they thinking". Man it's been a long winter.
 
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