Death to the RATTLE!

[vincejames]

I've had my XS for about 3yrs. replacing / upgrading as time / money allows. I've found (and I'm sure everyone agrees) the deathly rattle of these bikes cause a lot more harm than good. It's become customary that I tighten everything before I take my bike for a ride.

After a long talk with my mechanic who has 30+ years of experience working on 30s - 90s foreign bikes, we came to the conclusion that it might be a good idea to just sell my XS and go with something that simply rattles less. I've actually had my crank case rattle almost completely off, foot pegs come loose, carb completely pop off manifold.

Besides completely stripping the whole bike and locktiting every single bolt, I'm wondering if anyone on here has ever replaced things like motor mounts etc, to reduce the rattle. I know a re-phase is the obvious choice but I'm looking for a quicker more simpler fix.

Thanks
Vince

 

[vincejames]

Cut the losses and go with a better balanced engine?

 

[YamadudeXS650C]

I regularly ride my '76, which I completely dismantled and restored, and my '83, which I have upgraded and repaired. I haven't used any loctite, but have replaced many of the fatigued lock washers. Some of my rides, like today's, last 4 hours, and I reach rpms of 4500 and more. I have never had anything vibrate off.

I suggest that your bike is out of proper tune, and thus vibrating more than usual; I would check the timing first. The carbs popping off might be a timing issue, or the carb mounts may be worn out..

Also, make sure all of the fasteners are torqued to the proper spec using a good quality torque wrench.

 

[gggGary]

Part of the XS650's popularity is that it shakes like a "real" motorcycle should. I have had several nice late model bikes that are smooooooth and do everything well but are about as exciting as a refrigerator. I have been through more XS650's than most and if well fettled, the shaking is not bothersome to me. The rear fender., license plate, taillight do get beat up a bit due to their being way out on a long lever that accentuates the vibration. I have learned to back the licence plate with an old plate with a bit of silicone adhesive between them, problem solved. Shaking is part of many if not all twins that don't have balancer shafts. I don't really have issues with properly tightened parts working loose.
Carbs popping off is normally more of an ignition/backfire issue.

 

[grizld1]

+1, Gary! Vince, when I read the phrase "my mechanic," a red flag pops up right away. I don't question your guy's competence at all, but there's only so much a generalist can know about any particular motorcycle, only so much time and attention he can invest in any particular job, and only so much he can feel comfortable billing you. When it comes to vibration, the devil is in the details of cylinder and valve condition, ignition timing, carburetion, and motor mount fastener torque. Unless they have very deep pockets, owners of old bikes need to learn to do their own inspection and maintenance.

You haven't mentioned it, but with carbs popping out of the boots I'd guess that you have breaker point ignition and that the automatic timing unit is worn. There's been plenty written on this; search and you'll find.

 

[Royboy]

Vince, I totally agree with the above.
Just my opinion, based on a lot of motorcycles and a lot of miles. My XS's don't vibrate as much as the old Brit bikes and haven't ever shed parts due (with the exception of a couple of license plate bolts) to excessive vibration. If you are experiencing that level of shaking the bike is either badly out of tune or major mechanical failure is just around the corner.

roy