Bike pulling way too much to the left.
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Fast Eddie
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Is your front wheel rim dead central in the forks?
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It does sound like the rear wheel is not aligned with the front or it is cocked at an angle to the vertical plane of the bike. Both are quite possible on a Commando.
Do as suggested above and check if the front wheel is centred in the forks, then check, with two straight edges, if the rear wheel is in line.
With the bike off the stand, grab the end of the rear wheel and pull hard from side to side. This should show if there is play between the engine/gearbox/swinging arm and the frame. If there is play, it won't show up with the bike on the centre stand.
When I removed the rear mudguard on mine, only then could I see clearly that the rear wheel was cocked from the vertical (because the swinging arm was bent). And both wheels were offset to the right of the centre line of the bike.
Do as suggested above and check if the front wheel is centred in the forks, then check, with two straight edges, if the rear wheel is in line.
With the bike off the stand, grab the end of the rear wheel and pull hard from side to side. This should show if there is play between the engine/gearbox/swinging arm and the frame. If there is play, it won't show up with the bike on the centre stand.
When I removed the rear mudguard on mine, only then could I see clearly that the rear wheel was cocked from the vertical (because the swinging arm was bent). And both wheels were offset to the right of the centre line of the bike.
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Fast Eddie said:
And check your front hub offset.
If you run a straight edge across your wheels and you need to move the rear wheel too far off equal (usually TS too far forward) on the marks on the adjusters to align, then your front hub offset may be off.
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msh5337 said:
So your adjusters are now where they are recommended to be.
However, as L.A.B. stated, on a pre-Mk3 bike it doesn't matter which side they are on.
It seems to me that the manuals/installation instructions recommend the left front/right rear positioning of the adjusters purely for ease of access to them.
Having said that, I recall reading a discourse titled "The perfect Commando frame" or something like that. It was very lengthy and detailed and a lot of the alignment procedures in it have already been covered in this thread.
I think it was in this discourse that I read that both adjusters SHOULD be on the same side, because as adjustments are made, with adjusters on opposite sides , the engine/gearbox/rear wheel is pulled slightly out of alignment to the frame.
Of course I read this AFTER I had installed vernier adjusters on my 1970 bike.
I didn't bother to change them in light of this new info. The bike handles better than it did before. The old iso rubbers were like marshmallows.
concours
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TEST.... don't guess.
1) symptom: pulls to the LEFT.
Mechanic says a tire choice would do that? Doesn't pass through the bullshit screen, dismiss his credability. Whatever handling quirks a tire could cause would surely be exhibited in BOTH directions.
Wheel misalignment. You have to CHECK things and figure out WHAT is causing it. A gross error as described is usually noticable by eye. Barring that, get busy checking wheel alignment. Put the isos where they belong.
Has either wheel been re-laced? Offsets changed? (Accidentally/on purpose)
1) symptom: pulls to the LEFT.
Mechanic says a tire choice would do that? Doesn't pass through the bullshit screen, dismiss his credability. Whatever handling quirks a tire could cause would surely be exhibited in BOTH directions.
Wheel misalignment. You have to CHECK things and figure out WHAT is causing it. A gross error as described is usually noticable by eye. Barring that, get busy checking wheel alignment. Put the isos where they belong.
Has either wheel been re-laced? Offsets changed? (Accidentally/on purpose)
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CORRECTION:
In my previous post I said that your iso adjusters are now where they are supposed to be. WRONG. I should have taken the time to actually go and look at my bike before posting.
My vernier conversion on my 1970 bike puts them right front/left rear.
L.A.B. mentioned that the pre-Mk3 kits have equal length abutments, whereas Mk3 ones are unequal and require machining of the mounting tube for pre-Mk3 bikes.
If your kit had the unequal length abutments, then your left front setup could still be the culprit. Your original post seems to indicate that the handling problem only occurred AFTER the font iso was reversed.
I'm not sure which version the vernier kit I bought from Norvil is.
Looking back at my notes, the fixed abutment is 14.8mm long and the adjustable one is 13.5mm.
They are both slightly longer than the old shim type abutments and I had to machine 1.5mm from the mount.
However, if the distance between the frame lugs had been to book spec, the machining would not have been required (it was at least 2mm under spec.)
In my previous post I said that your iso adjusters are now where they are supposed to be. WRONG. I should have taken the time to actually go and look at my bike before posting.
My vernier conversion on my 1970 bike puts them right front/left rear.
L.A.B. mentioned that the pre-Mk3 kits have equal length abutments, whereas Mk3 ones are unequal and require machining of the mounting tube for pre-Mk3 bikes.
If your kit had the unequal length abutments, then your left front setup could still be the culprit. Your original post seems to indicate that the handling problem only occurred AFTER the font iso was reversed.
I'm not sure which version the vernier kit I bought from Norvil is.
Looking back at my notes, the fixed abutment is 14.8mm long and the adjustable one is 13.5mm.
They are both slightly longer than the old shim type abutments and I had to machine 1.5mm from the mount.
However, if the distance between the frame lugs had been to book spec, the machining would not have been required (it was at least 2mm under spec.)
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