Adventure Trail Bike Forum

The 'Stannard Method' of repairing worn output shaft spines.

So I've been following, or at least trying to follow a jumble of rather interesting posts by Andy regarding a modification to his Transalp output shaft previously considered by many owners as impossible.

I figured I would post it here to A. Make it easier for me to read and B. As reference for any other TA owners that fancy undertaking this mod.

Please note that all of the following is written by Andy, I've simply copied and pasted it across from XRV.

I have just joined the site, so am a newbee, but my bike has recently done the same noises and knocking through the footpegs...and it definitely " IS " wear between front drive sprocket and the splined driveshaft. Sprocket has most wear, about 75% of the slack, well worn, and leaving about .018" thou wear on the splines measured when a new sprocket is fitted...NOT NICE...but nowhere as bad as some images i have found doing google'ing. I am in the process of sorting it, and it seems a common failing of these machines and other bikes with the same retaining method.....will post results of my particular repair method later. Am fitting new chain and sprockets at the same time, which did fix the problem, but my repair should stop any further shaft wear...and it does NOT involve permanently welding a sprocket on either. Will be in touch on here again....Andy

Hi All....Anybody out there that is interested ?.... I have drilled and tapped the output driveshaft centre for a 6mm x 1mm standard pitch thread to a depth of 19mm. My intensions are to increase the sprocket width to 22.7mm ; two bolted and spot welded together after removing the teeth of the outer one, and retain it with a thick 30mm washer and high tensile caphead bolt, 243 loctited and wirelocked to the two capheads bolting the sprockets together. This hopefully ? will fix Mr Honda's very amazingly bad bit of engineering...which propably saved him a few quid ! but caused lots of people grief and bike scrappage. This is going to utilize the last bit of spline on the shaft and be wide enough to stop any future wobble come slide wear. Will carry on posting results...by for now.....ANY BODY INTERESTED ? Lots of other bikes out there with the silly splined misaligned washer idea, so not just transalps.....

Hi Saxal & Shandrinker.....Thanks for reply...I have just tried to upload a few pics of my wear on shaft without and with a new sprocket on, and the tapped shaft, bolt and washer in place. BUT couldn't do it. Will find a younger more competent PC buddy to have a go at a later date, and am still trying to find where I have hidden the pics of my very temporary shimming up of the wear gaps with cut up feeler gauges that allowed me to stop the knocking and ride out for a couple of miles to prove the idea will work.....keep an eye open for them...they will go on eventually. Have not welded the sprockets yet either as 2nd spacer sprocket not modified yet, needs milling to thickness and teeth off. I have the special rods though that are supposed to do the high carbon steel ? without cracking them ? Used to be a bloody good welder, but never this stuff, but hope to show a good job pics later.....by for now....I'm in Essex....

Hi Phil.......short version...alignment drill jig, solid carbon drills 5mm and 6.5mm for case hardening, then Guring SUG's for pilots when through hard stuff, NOT a carbon tap though...may have broke..bloody slow and careful...by the way i'm in engineering...chain alignment exactly as original using an original 3.15 mm retaining washer behind drive sprocket, this will do away with all end float....

Hi all...Still slowly getting my modification on the go. Drilled output shaft end tapped to 6mm x 19mm long thread. Machined a same size splined thinner sprocket to fit flush to shaft end that has same fixing bolt spacing. Next job to bolt and weld together for extra width and drive. I am shimming up the slight wear and will be bonding new wider sprocket to shaft. High temsile caphead bolts, all drilled for wire locking are going to hold it secure. Will add more photo's later as I go....if anyone is interested....

Hi...especially Phil....have done a bit of the shimming up on the shaft using .006" thou. Looks like it will be .010" next as the .012" wouldn't all fit and locked the sprocket on. Just found a bit of time to play with it a bit more. Am making up a 2nd modded sprocket as a spare for the future. Putting on a few pics of the machined extra sprocket and original as comparison for others to see what i'm up to at present. Bit slow; but coming along as planned so far...i'll be back....Andy...

Above...

Wider sprocket set compared to original.....

Then .006" thou shims bonded on..... (EC edit: zoom in to see shims!)

Next is the .010" shims rested in place to check fit. (EC edit: better than porn this pic - look very carefully folks, I didn't spot the shims on the first glance!)

Dry trial run .010 thou pre bonding and brilliant, has less slack / play than shaft front that's got no wear....ALL LOOKING WELL....it will hold, but for how many thousand mile ? Final .010 thou shims bonding in place as I write, I used the driving sprocket to push the little buggers hard against the prebonded .006 thou to make sure I had some clearance to slide fit on and off. Locked it all on and in place with the original retainer splined washer while it set overnight. Photo to follow of finished shimming...looks really good........