The current bolt is an M8, yes? The allen nut solution MIGHT work if the adjuster bolt were an M6 and the odds are even better with an M5 bolt as we are gaining clearance from the threads of the adjuster to the starter motor as the bolt gets skinnier (assuming allen nut outside diameter gets smaller with bolt size getting smaller.
There is essentially almost no clearance from the adjuster thread to the bolt on the housing of starter motor. Its fortuitous that the starter motor sinks in at that location, otherwise, I don't see an type of simple elegant solutions beside the stock tensioner.
As long as you can find an long allen bolt with same (or smaller) outside diameter of the CURRENT threaded adjuster bolt, it will clear—anything larger in diameter is no good (ala acorn nut). Anything shorter doesn't really help because the clearance issue starts 2–3mm after the jam nut in the pictures I sent.
Another thought is that if the housing could be half the thickness of the current one that would help gain you some clearance?
Originally Posted by markk53
I looked at the pictures, but am not totally sure if I am seeing things as I think I am. I may have a solution I use on the KLX250. I use an allen nut from a Yamaha SR500 exhaust - IF there is any clearance for it. It is 13mm in diameter, I am not sure I see that much clearance there in the pictures so you will have to let me know. I can turn the nut down tight against the end of the bolt and with a dab of blue LocTite on the thread it should stay put. I can also use a shorter bolt since it appears…