HOME and how to join Forum Open Area General Scott topics Brum Engine Drive Chain Spring Link Re: Re: Brum Engine Drive Chain Spring Link


Don’t run the bike with the tight chain/cracked link !! This can loosen the drive sprocket on the flywheel, which is a total engine strip-down job to put right. To adjust the chain first slacken the two nuts holding the final drive outrigger to the gearbox tray, then the two nuts underneath the tray that hold the gearbox in place. Now go to the adjuster sleeve-nut on the rear right-hand side of the tray, and turn it anti-clockwise, which will push the gearbox forwards and so slacken the chain, to give you a good inch of up and down play in the chain. Tighten the two nuts under the tray, and then the two outrigger nuts. Recheck the free play in the chain.
This procedure will have tightened the rear final drive chain, which will then also need adjustment by slackening off the rear wheel spindle nuts and then slackening off the two locknuts on the adjacent adjusters, to allow the wheel to go forwards, then tighten the wheel spindle nuts and finally the locknuts on the adjusters.
Finally check that the back wheel is still in alignment, by means of a length of string or a straightedge placed alongside both wheels, about four inches off the floor. NEVER run the bike with tight chains……
“Sprockets Unlimited” can advise you on all things chain, and supply everything you need. Obviously the new link needs to be the same make as the chain, which would originally have been Renold, not to be confused with Reynold or Reynolds…