Originally Posted by BlueLghtning
Most people gear their bikes like a 13/45 - 13/49 depending on their preference. However, another popular gearing is going up to a 14 front and running like 14/50 or something like that. This also helps keep the chain away from the swingarm. If you were running 14/50, you can easily drop to a 13 if you feel like without taking out a link and that leaves you at 13/50 which is pretty low gearing.
IMHO, this is the best option. Yes, you need a longer chain to set it up ... but once set up you've got gearing options ... by simply swapping out front sprockets and adjusting chain slightly: 14/50 for road riding, 13/50 for trails ... and 12/50 if things get really knarly. We do a similar set up on the DR650's ... and we switch between a 16T, 15T and 14T ... all with a larger rear sprocket. Works perfectly and covers a WIDE range of gearing.
Someone could work out the Math and compare these options to stock ratios ... and go from there.
Originally Posted by 8gv
Thanks for the insight on this. Has some entrepreneur developed an alternative swing arm protector? I saw a pretty ugly picture of what can happen when the chain rubs there.
The WR, like most dual sports, has a thick rubber, wrap around swing arm protector. When it shows deep grooves ... its time to replace it. Not that big of a deal. If you ride A LOT of aggressive off road the chain will rub through the rubber protector eventually. Normal wear and tear.
Originally Posted by HardWorkingDog
My belief is that swingarm damage can caused by
1. Too tight of a chain.
2. A small (12 tooth) front sprocket.
3. A loose and poorly lubricated chain that has links that are kinked.
4. Too much weight on the bike (max. load rating is 408 lbs.).
None of these things alone are sufficient to cause swingarm damage, as there are lots of owners out there running 12 tooth sprockets, tight chains, loose kinked chains, etc. without suffering damage. I think the biggest contributing factor is a combination of one or more of these along with riding long distances with lots of obstacles.
Do I think this is a "design flaw?" Nope, it's a maintenance issue. If you keep the chain well-maintained, keep the slack adjustment correct, don't overload the bike, and stay with the stock 13 tooth sprocket you're not going to have this problem. I would buy a spare seal guard (Yamaha-ese for the swingarm protector) and take it with me on any long trips--it's a wear item.
Excellent summation of this issue!
I tend to agree ... that it's not a great idea to go with a front sprocket smaller than 13T. Smaller will wear chain more quickly ... chain must make a sharp U Turn around the smaller sprocket ... hard on chain ... and may rub on rubber swing arm protector.