Apex turbo gearing?

[M5-]

DooTraxx if you do a search on snowest of 18-40 gearing you will see guys have broken chains and slack adjuster i do not know the hp to do this damage but i do know this hp is not going to the track.
18-42 is available with reverse and non the ratio is very close but your chain/brake system is running with the efficiency of a 20-40 set up.

Just a heads up to anyone looking for the 42 reverse gear. It was only made by MPI and in order to run one you need to have the idler wheel machined down because the idler gear contacts the 42 tooth reverse bottom gear, I can post pictures of the problem if I can find them. Been there tried that, a Yami chain stateside is 95 bucks, pretty cheap insurance. I've seen zero chain failures with the 18, but lots of chain failures due to guys cheaping out and running after market chains. The stock Yami Hyvo is a pretty stout chain.


M5

 

[DooTraxx]

I am not very concerned with running the 18 tooth. Maintenance I am sure is key but if summittboy can beat on it all season with no trouble I am sure I will be fine. Belt life will definately be nice.

 

[DooTraxx]

Not to mention my sled came with an18 top gear. Pretty sure if the Yamaha engineers think its ok it will be fine. After all they have a pretty good track record of not using marginal parts lol.

 

[boost mod]

Are these Yamaha engineers the same ones that put the brakes on the top shaft? Because it would have been nice never to have to worry about brakes failing. Maybe if they do a redesign, they will put it on the bottom shaft then chain failure will not affect safety.

 

[summitboy]

Boost Mod, your on this thread preaching safety and you ride a sled that has more horsepower than most cars on the road with seat belts ? Maybe you can write Yamaha and explain your situation and let them know that you think their engineering is all wrong and unsafe.

I'd like to know how many chains you have personally seen break since you have been riding Yamaha ? In our group we have 20+ turbos. Some have been riding them for 16,000km. I have seen 3 failures in our group in the last 9 years:

1. Turbo RX1- owner rides until chit breaks ! (He rides 100+ days a year)
2. Turbo Nytro - owner assembled case incorrectly (chain lasted all season before it let go)
4. Turbo Apex 14,000km- my sled had a chain almost come apart (used a cheap aftermarket chain which lasted a 1/2 season running 19/40)

Out of all the chains i saw break not just Yamaha but Doo the track always locked solid. I don't ride around the cabin amongst 200 sleds for it to be a issue even if by some crazy miracle the chain breaks ! Braking has never been a issue period in 7 years of riding my Pex !

This thread is about gearing/clutching a sled to stop belt heat. How many days/km do you actually have on your unsafe Yamaha ? Your a little off base LOL

 

[sledfvr]

I agree with you summitboy. I don't shut my sled off ever and it's to the bar all day. I blow belts when most other people wouldn't. My 174x3" blew a few last year and if it does it anymore then I'm gonna try gearing down too. I think having plenty of weight in the tip of the primary weight and a 2-3 wrap on the secondary will help.

 

[boost mod]

summitboy you're entitled to your opinion like you say that your group has never had any big problem it sound like you sled with good guys. i have seen an apex break a chain in golden he was not with our group. he was part way up the hill when it blew he fell off it on the way down it kept going and it hit another group the second sled it hit had a woman on it she had to get air lifted out i am not a safety nut but when this happens your view of thing change. sorry if my concerns with this mod and yamaha braking system is over bearing i am sure with your knowledge this will not happen to you but seeing this happen and having to stop fights (very mad husband)and trying to find help sucks just about as much.