How do you know if a rear sprocket is bad?

[Tyson82]

Hey all.

My brother just picked up an 81 550L. The guy he got it from said that it needed front and rear sprockets. We pulled the rear wheel off tonight and were looking at the rear sprocket. Im not sure what Im looking for, but it didn't seem all that bad. The teeth are a little pointier that the sprocket on my 450T, but otherwise seemed to be in similar shape.

What do you look for when determining a need to replace a sproket?

Thanks

[TheCafeKid]

You look for twisting of the teeth, high teeth, hooked teeth, or just overly worn teeth. Look down the teeth as if your field of vision were the chain. Honestly, if you have any question on the integrity of the sprocket, replace it. They arent that expensive, and running a worn sprocket will only cost you MORE money in the long run by ruining a good chain, or worse yet, a nice fat hospital bill, and a wrecked bike were it to snap the chain while at high speed. Its simply not worth it to keep a questionable sprocket.

[Tyson82]

hmm.

Well I wouldn't say that any of the teeth are twisted or any of that. I just hate to spend the $70 if I don't have too.

[TheCafeKid]

70 bucks???? Where on earth are you buying sprockets?? I think you could nearly do a complete 530 chain and sprocket conversion for 70 bucks. Check out Z1Enterprises.com for a sprocket bro, no more than 40 for sure, if that much. 70 bucks...WOW. Seriously tho, I have had many an experience with continuing to foolish use a worn sprocket, the last of which nearly wrecked me when the chain bound and pull the rear end sideways. It then fell apart in my hand. Get a new sprocket man.

[Tyson82]

Thats definately better. Bike Bandit was asking $61 + shipping.
Thanks for the referal.

[TheCafeKid]

Thats definately better. Bike Bandit was asking $61 + shipping.
Thanks for the referal.

Ahhh likely b/c its an actual Zook OEM sprocket. Not a big deal to use an aftermarket sprocket. I have found them to wear just as well, if not better, and certainly cheaper. I just picked up a 530 front and rear from Z1 and i think i paid less than 70 for both shipped, and I have no doubt they will last as long as the stocker that was on it. Incidentally, what size is the stock sprocket on the 550? I want to think it was in the 50ish range. If so, im not sure if the hub pattern is the same on the 750 as the 550, but i have a 52 tooth 630 sprocket, and a 41 tooth 630 sprocket that i have no use for now. I swapped to 530.

[Tyson82]

OEM is a 49 tooth 530.
Bike Bandit does have aftermarket sprockets, but the cheapest one is still $45 + shipping. Glad you mentioned Z1.

[TheCafeKid]

huh, i didnt realize they used 530 on the 550s...Learn something new every day No prob on the referal. I love those guys, and try to do ALL my parts shopping there whenever possible. If you have questions, give them a ring, they are VERY helpfull, and know most of these UJMs inside and out. I use BikeBandit pretty frequently too, but Z1 sells nothing BUT vintage parts, so they know what they are talking about, rather than refering to a shop guide or OEM parts catalogue. They are also probably the fastest business i have ever worked with as far as shipping goes. And whatever parts you see on their site are IN STOCK, and usually ship that day, rather than being ordered from Suzuki, or another parts source.

[Steve]

Another way to evaluate your chain and sprocket is to try to lift the chain away from the back of the rear sprocket. If you can see daylight between the chain and sprocket, it's definitely time to change them both. Actually, all three, as you will probably want to change the front sprocket as well. 8-[

.

[Nessism]

Z1 is definetly a forum favorite around here.

FYI: Chains and sprockets are typically changed together because they wear together. It doesn't make sense to put new sprockets on a bike with an old chain.

[lurch12_2000]

Another way to evaluate your chain and sprocket is to try to lift the chain away from the back of the rear sprocket. If you can see daylight between the chain and sprocket, it's definitely time to change them both. Actually, all three, as you will probably want to change the front sprocket as well. 8-[

.

Another way is to carry a passenger, rev the engine, drop the clutch and see if the front wheel lifts or if the chain jumps the sprocket first.:-D If the latter then change the sprocket!
Another way... the manual tells you how to measure the end points of the sprocket teeth and if they are worn below specs then change it.

[Tyson82]

Thanks for all the info guys.