So today I decided to check and adjust the wheel drive chain. I tightened the chain tension and checked freeplay. Noticed when I rotated the wheel 1 turn and checked freeplay again the chain was much much tighter. What would cause that? I dont know how long that chain has been on the bike and I plan to replace it. Is it safe to ride like that? Will it cause long term damage?
The chain became tighter because the sprockets are worn, and no longer round. You should always rotate the rear wheel to find where the chain is tightest, and adjust the chain at that wheel position. Otherwise, the chain will be too tight right there, when riding. This can cause bearings or the chain to fail. Chances are, the chain is too old also. Now, you would very likely need to replace the chain and both sprockets. I suggest using an O-ring or X-ring chain, with the same number of links as you find in the old chain. Your new sprockets should have the same number of teeth as the old ones. This new chain technology will last much longer than any old-school drive chain. Ask here, rather than changing sprocket sizes by guesswork, if you want to change your "gearing." Somebody here may chime in with specific products to give you the best results.
Intermittent chain tightness is usually cause by a "sticking" link. Once that occurs I've never been able to unstick the link, I think the captured lube is gone and the chain is toast.
When chains break, they can simply fall off the bike. Or they can wrap around the front shaft and likely crack the case. The cracked case is a two part problem. 1) The sudden addition of engine oil dropping right in front of your rear tire while you are at some speed. 2) The cracked case, your bike will need help getting home.
Appreciate the input from yall. Any suggestions on chain mfg, and strength. Also want lower rpm at higher speeds. How to accomplish?
Quote from: Jpn on July 18, 2025, 12:47:02 PMAppreciate the input from yall. Any suggestions on chain mfg, and strength. Also want lower rpm at higher speeds. How to accomplish?
I prefer DID or Tsubaki and lean towards their premium chains.
Might as well replace sprockets, order the whole kit from Randy, he can also suggest gearing changes.
Me, I always ended up going back to stock gearing.
Appreciate the info, thank you.
RPM sells what I think is the strongest chain. Remember you need the chain tool as well.
If you're getting sprockets too I just switched from stock (17T/41T) to 18T front and 40T rear and like it a lot better. Still plenty of grunt on the low end but gears are longer now so don't have to switch gears as much. I found stock gearing too low.
https://www.rpmracingca.com/proddetail.asp?prod=DIDChain
:good2: :good2: Yep, RPM sells the best. DID ZVMx is my go to chain.
I also find the 18/40 sprocket combo my favorite.
Don't get a cheap chain for your FJ. Invest in quality.
I'm with Pat on the DID ZVMx Heavy Duty chain - and ALWAYS put new sprockets on with a new chain on your FJ.
I'd go one step further on the sprockets and go for 18 teeth at the gearbox and 38 teeth at the rear wheel. This gives a much more relaxed highway cruising speed rpm and still doesn't spoil the FJ's ability to pull top gear, or overtake without downshifting.
On 18:38, 70mph is just over 4,000rpm in 5th gear. :good2:
I can also personally vouch for the DID chains. Wonderful and long lasting. Use proper tools to rivet the new chain or get it done at a shop.
Recently got myself a DID 530 VX3 110 link chain with a riveted type link.
Regarding gears, I recently switched from 17-39 to 18-38 sprockets, front from a maker called Sunstar, and a rear 4CC-25438-something.
Sorry for the repeat...
Go new with sprockets and chains, or one or the other will wear faster due to the older components.
As far as gearing is concerned,
This is as low i would suggest anyone should (probably can?) go. 18 teeth on the front and 38 on the rear will give you a nice low rpm when cruising. You'll loose some low end, noticeably, but it's good for long tour.