do i need straight cut gears?

[drake]

i plan on building a 421 cub motor. and was wondering if i need straight cut gears or will the stock gear hold up.its not going to be an all out drag bike

[alcoholbanshee]

Stock gear will be just fine....... I have a 421 cub drag bike with nitrous and still have the stock gear.

[Koolguyson]

straight cut gears only take the side load off the bearing.

[lonestar]

I'd put them in. Alot people don't realise how inportant they are. Yes you can run the stock gears. But you will be wrenching on it sooner or later. You can screw up your crank seals & possibly ruin your cases. Yes they are exspensive 460.00 shipped from this guy Piranha from planet sand web site. These gears are drop in units,with the bronze bushing already machined inside the main clutch gear.No screwing around with your old one. He only makes stock gear ratios. This guy is cool. Its just better insurance. For 460.00 its worth it you get both gears. Ready to install It's up to you. When i installed mine they do make a little noise. Not bad though. Yamaha should have made them like this in the first place. They arent that loud. I kinda like the noise they make.