Has anyone else had a problem with gas in the tank contracting and causing it to vapor lock?
Not a big problem to unscrew the cap, but just the same I was wondering if anybody had run into the problem.

 

Not sure why they vapor lock, havent experienced it yet on my 03 grizz, but yamaha has made a ratching gas cap similar to a automotive for the 04's, seems it has to do with tightening the cap too tight, kinda makes you wonder why the cap has a vent tube, hmmmmm[img]i/expressions/face-icon-small-confused.gif[/img]

 

Your not the only one.

Check Here:

http://atvnation.infopop.cc/6/ubb.x?...2&m=1406099564

 

it happens. NOt everyone gets it, but the people that do are very vocal about and make it seem like an epidemic (not that I wouldn't do the same!)

I have never experienced it myself.

 

While on our ATVenture vacation trip to the high Colorado Rockies in July, only 1 of the 3 Grizz '02 660's suffer from a vapor lock & that was after a long steep 4 mile 2000 ft. elevation climb up a gulch, where we stopped for a break at a very steep hill climb. The other 2 660's had their air-cleaner lids off, since those 2 660's were not jetted for the higher elevations & by having the lids off might have allowed the trap hot air/gases to escape. The vapor lock 660 was jetted correctly but after the long steep 4 mile climb, it sat with the engine off for amount 30 minutes & the air-cleaner lid was on. At the bottom of this very steep hill climb & at the 12,000 ft elevation, this 660 suffer a vapor lock but just by revving the motor a bit while in neutral & cleaning out the vapors, this 660 climb the hill climb with ease. This same 660 never did have another vapor lock the rest of the entire trip.
I noticed that the '04 Grizz 660's have vents on the side panels, no doubt that the folks at Yamaha have looked into the vapor lock problem on some of the Grizz's & came up with a solution.

 

Check out 3TV's posting from a different thread here.

 

If our Griz ever gets rolled,,,,,,,here comes the gas. That dang check ball is out of there. Thank you 2TV & 3TV. I thought about removing the check before your reading your post but after the read the removal was a done deal.