Doing routine maintenance I noticed a wear line in the sidewall of the 3.50 x19 rear tyre. It is in line with the forward chainguard fixing. A further check revealed that the tyre is not perfectly central to the adjacent upper curved rear frame sections. Possibly by about 3/16". I built the wheel to be central between the shocks and the bike has always been the best handler even when compared to other beds. I'm beginning to think the wheel is offset towards the drive side.Too cold (read old) to go grovelling down there to check wheels in alignment. I'm wondering if I line things up perfectly with spoke adjustments will I finish up with a bad handler just like the Thruxton 500 mile race winning 650SS that really needed wheels offset to the left to counter the heavy clutch and alternator load. Normally I just think about thinking about it ! ,but this cannot be left any longer. O dear, Action needed.
It's not rubbing on the inside front left of the mudguard is it? The small flat square part visible on mine is cut away on later bikes. There's just about the thickness of a credit card between my tyre and the mudguard with the wheels as near in line as I am able to measure them.
Hi David, No I dont have that type of guard. And yours nearly rubs because you have somehow managed (just!) to fit a modern tyre , Would not go at all in mine. I still slip and slide on the old SM although it is superior to a modern tyre when on gravelly mud.( Henfold lake run!) as it has a deep tread. And it seems to last forever till it goes hard. I have fudged the issue by twisting the wheel in the frame so the wheels are no longer in line. Its going to have to wait till i get my new hydraulic bench up and working in my heated workshop ( a lifelong dream now on my bucket list) , now a possibility as I am now resigned to paying for it to happen.
Restoring my 62 Slimline 99 and i noticed the tyre is closer the top left shock nut by about the amount you mentioned. Thought at first swingarm was twisted making wheel lean over but when i removed shocks the centres of the shock mount holes were bob on the same. It’s a bit odd. To check wheel is straight I measured from swingarm spindle to rear wheel spindle, got them the same and the tyre was dead centre of swingarm at the front.
I think this issue could provoke a lively debate!, My gut feeling is that the best handling slimline road bikes will be those that have the rims offset a little to the left to counter the heavy alternator and clutch which are stuck out there and also providing a centrifuge effect . Perhaps the wideline with its centrally mounted dynamo and lighter clutch does not need the offset. There are those who say the widelines are better handlers ,maybe they are right. I can only make the comparison between out Atlas and the 60 99DL(both slimline) . There is a vast difference. The 99 positively turns like a dancer and can be ridden with the tyres sliding all over the place ,flung into corners and change line mid corner. By comparison the Atlas is like the Titanic , no chance of recovery in a tightening corner without heavy counter steering and weight transfer to footrests. Still ,it gives me something to ponder over.