GS450E chain noise

[Anonymous]

So the old GS450E is mobile. The Dunlop tires don't look cracked and hold air, but they're at least 5 years old and have been sitting, so I want to replace them. The brakes could probably use service (rear drum squeals sometimes, front brake is kinda soft) and that chain is of unknown age, not to mention the rear sprocket seems to have a tiny bit of wobble to it. The wheel doesn't wobble, but the sprocket does. Weird!

One thing I've noticed while creeping it around the neighborhood (just have to ride it a little bit! ) is a random bit of chain noise, metal-on-metal clicking and clacking now and again, like the chain is touching against something. There is an aftermarket chain guard which has about a half inch of clearance between itself and the top of the chain. Maybe the chain is touching it?

[jtcrespo]

If the sprocket wobbles, then that is not good news for the chain and could cause the sound you are hearing. More than likely there is now a kink in the chain from sitting so long. You can work with the chain and possibly get it out, but I would replace the chain and both sprockets just to be on the safe side.

[Anonymous]

If the sprocket wobbles, then that is not good news for the chain and could cause the sound you are hearing. More than likely there is now a kink in the chain from sitting so long. You can work with the chain and possibly get it out, but I would replace the chain and both sprockets just to be on the safe side.

It is a very mild wobble, but I've already committed to changing it -- as soon as I raise the money and finish flip-flopping over whether I want a rear sprocket one or two teeth smaller, etc. It makes sense, do it all at once: tires, chain, sprocket, brakes. $$$, but at least it'll be done. 8O

I would like to drop the revs while cruising -- though I have not done more than some brief 'round the block driving (going easy on those old parts!), I did push up to 50mph once (bad!) and noted from that run that the motor has to turn over pretty fast to do highway speed. On the flip side, I don't want to bog the motor, either, forcing it to run slower at higher speed if it doesn't have the guts to handle it. I wonder if any of you 450cc'rs have done this and can offer insight.

[IanFrancisco]

These bikes have a cush drive in the rear which is why the sprocket can wobble while the wheel is solid. Check bikebandit.com for fiche pics. The sprocket should not wobble much at all, though. A tiny amount (less than 1mm) is probably OK. Replacing the chain and sprockets will be a waste of money until the wobble issue is resolved. My GS450ST had a different chain noise which turned out to be from the camchain tensioner not doing its job. Needed another 1/2 turn on the spring. Check elsewhere in the forums for more info on that. The GS450S models have a larger 43 or 44 tooth sprocket in the rear to boost acceleration. I think the other models have a 41 tooth rear. All models had a 16 tooth front from the factory. Of course who knows who's done what in 20+ yrs.? My bike ('80 GS450ST) is turning over about 6000rpm at an indicated 65mph and about 7000rpm at 80mph, kinda busy but tolerable. I think I'm running 16 front/44 rear. These engines should be able to run at 8000rpm all day without harm if they're healthy and cool (~200-230F oil temp) and redline is 9000. I've read stories on a UK site (http://www.umgweb.com/) about guys who run these GS450's at 85-90mph for 75,000 miles without breaking them, but Your Mileage May Vary Two ~225cc pistons will not provide monstrous amounts of torque at low/midrange rpms. The motor makes it max horsepower at redline, 9000rpm. I wouldn't gear any taller than the L models (16/41). If you want more acceleration, go ahead and go with 16/43 or 16/44. These 450's aren't lightning fast anyway. The UMG site says that the left exhaust valve is a weak point on these "unburstable" motors, they tend to burn up first, maybe due to the casting or air flow characteristics. Makes a good case for using synthetic oil once the rings are well seated.

[bgmart450]

450E stock sprockets = 16/45
530 chain 104 links.

Same for S's

The stock 450L is 16/41
and the 450TX, TXD is 16/43

Been thinking of dropping a few teeth on the rear of my E.

[Anonymous]

Half an inch is way too close to the chain. I just looked at my 1100E and it has over 1.5" of clearance when the chain is in its natural position. That makes sense since you set the slack to be more than 1/2". You may also have some loose and tight sections of chain. Find the tightest section of chain and set the slack at this point.

Steve

[Anonymous]

Thank you all, this was the sort of info I was digging for! I'll look into the cush drive about the wobble and see if I can't get more clearance between the chain and chain guard. That's something simple to try to see if the clinking noise goes away.

The maintenence history of the bike is unknown, so it could need a full service. The cush rubber could be old and stiff at this point. As long as the rear wheel was getting dropped for a new tire, I was thinking of just getting it all done at once: rear sprocket, chain, rear brake, rear shocks/springs...and I wouldn't doubt if something else needs replacing. I'd like to get a MAC 2-1 exhaust...the stock exhaust is solid, but cosmetically poor. It'd improve the looks a good bit.

That's a good chunk to spend, but it's such a fun little bike...I think it's worth it. I tend to keep my "first" when I can. I'll be glad down the road.