question about my 490.

[prater696]

Hey fellas.
I have a 1984 yz 490.
Someone suggested that I remove the air induction box from the gas tank and plug the hole in the carb. intake boot. The reason is he said if that box ever cracks it cound make a disaster out of the top end. All of that makes sense but is that a common problem for these bikes and if so what do people use to plug the hose connector on the intake boot? I assumed maybe the same sized diameter bolt and a hose clamp but right now this bike has no air leaks and I would hate to cause one by doing this.
Any suggestions from someone who's done this or just knows about this stuff is appreciated. Thanks...~Matt

 

[zoommx]

Personally I'd leave it as is, in fact I did leave it as was on my '82 before I sold it last year. I never thought of it cracking, but if it had, the bike would've started running much differently and I would've found the problem before trashing anything.

 

[Fixitguy74]

My 81 250 had one and the intake boot was dry rotted and cracked when I got it and the part is discontinued. I did a little research and found in my case that 81 was the only year Yamaha put it on a 250, but the 1980 model was very similar and the intake boot was still available. It fit perfectly. It was just missing the boost bottle port on the top. The bike runs fine, maybe a little rich with stock jetting. So if it becomes a problem in the future you might get lucky with a little research.