Slightly twisted front end

Status
Not open for further replies.
Joined
Jan 8, 2006
Messages
46
Hi All, I have discussed this one before and have had no success so far. My Mk111 has a slight twist in the front end, after I tried several methods suggested on this site, ie loosening all and pumping front end, I still have a "bend" somewhere (checked bars - not bent) The previous owner installed new fork tubes and the trees look new also. Any other suggestions please. Are the trees keyed together, ie, can't be out of alignment??
 
Joined
Mar 19, 2005
Messages
696
If you can see the "twist" with your eyes..check everything through again, measure and give the tricks mentioned another try. Get a helper to eyeball everything when you try to twist it straight. If it won't settle in straight by itself, though, using the tricks mentioned, and you have to force it, something is bent, or you didn't loosen everything you should have. Top nuts, (tap tubes loose from upper tree), bottom tree pinch bolts and center nut, fender stays and brackets, axle nut, axle pinch bolt...everything just a bit loose. Wiggle bars left and right and let them settle into a midpoint and pump it up and down from the riding position, and stay sitting on it, keep it upright and let somone else start to tighten the items, top to bottom. My bottom tree is not keyed, but mine is a MK1..Mk3 might be different. Don't forget to tighten ANY of the items you loosened, or we will be reading about you in the news.
If you can't see the problem, but just notice the problem when you drive, check isos, check top motor mount, check action of the sliders, oil content of the forks, swing arm, rear shocks, etc. Any number of things will cause a bike to not drive straight.
 

L.A.B.

Moderator
VIP MEMBER
Joined
Nov 20, 2004
Messages
18,709
Country flag
vince said:
Are the trees keyed together, ie, can't be out of alignment??
=No.


Have you checked that you have a matching pair of yokes (trees) as 750 and 850 types are slightly different and shouldn't be mixed (or used as a pair on the wrong frame)?
850 yokes should have 'ANG' (and a number) cast into the underside. The upper 850 MkIII yoke of course is easily identifiable by the two warning light console mounting lugs.

I don't bother loosening the upper yoke top nuts as I don't think it's possible to pull the stanchions (fork tubes) up into the tapers misaligned, in fact it may help with alignment to keep these tight.
 
Joined
Mar 19, 2005
Messages
696
I don't bother loosening the upper yoke top nuts as I don't think it's possible to pull the stanchions (fork tubes) up into the tapers misaligned, in fact it may help with alignment to keep these tight.

LAB....might have a valid point there :wink:
 
Joined
Jan 15, 2006
Messages
54
The reason to loosen the top tube nuts is to be able to rotate the tubes to check for bends. Use a marker or bit of tape to give a reference for how much rotation you are getting. You will be looking for movement in the leg/wheel area. Sometimes this can be seen with wheel mounted, sometimes you must remove the wheel and look for it at the axle end. Keep the tube pushed up into the top tree taper (nut just a little loose) to avoid creating movement. Final check (besides pulling the tubes out of the legs for measurement) is to undue the top caps and slide the leg up and down to check for binding.
Just remember, every single part of the front end can be bent, including the legs. If you can't put a straight edge on a part, then you check for binding in normal movement or during assembly/disassembly.
 
Status
Not open for further replies.
Top