Trying The 8DN BELT

[YamahaTim]

Well Stud its good to hear your going ballistic!!! you say you won't need more than 6#'s HA I say you'll always want more!!! Be Careful though more than a few of us have had problems at 6#'s. The AFR #'s are important only problem is trying to read the thing when you are standing on the tail. When Yamaha Tim and I first got our sleds we added guages and found them at about 3.5 to 4 lbs of boost. Mine started having problems at that rate of boost and finally blew up even with #'s under 10.5 on the AFR. Mine now can go to 12# but I need race fuel even with the 0 compression wiseco pistons 9 #'s is awesome. As far as the 8DN vs the stock belt I had no problems at under 6#'s of boost but after the rebuild and cranking it to 7 and 9 on the switch I started blowing belts at under 200 miles. I went through 3 in 2 weekends so I am changing mine over next weekend. I finally got it back after being in the shop for 3 months for failed handwarmers, and no lights on the gauge pod.

You are alive...lol...man I hate being busy!! You must be swimming in work. I'll call ya sometime this weekend to see what's up...ya your belt lasted a lot longer than mine, remember in houghton when I blew my first one? Then going to the hoop an hollar when I broke my 4th one.

 

[Yamadog]

You are correct sir! but had to add my 2 cents on this. Finally got mine back, such a load on those simmons it would not come off the trailer. I had to tie a rope to it and drag it out. Gonna have to come up with something different on the front!

 

[YamahaTim]

You are correct sir! but had to add my 2 cents on this. Finally got mine back, such a load on those simmons it would not come off the trailer. I had to tie a rope to it and drag it out. Gonna have to come up with something different on the front!

Ya, I have ridden that thing, you definitely need to change something!! Or start lifting weights now...lol...

 

[stingray719]

Well Stud its good to hear your going ballistic!!! you say you won't need more than 6#'s HA I say you'll always want more!!! Be Careful though more than a few of us have had problems at 6#'s. The AFR #'s are important only problem is trying to read the thing when you are standing on the tail. When Yamaha Tim and I first got our sleds we added guages and found them at about 3.5 to 4 lbs of boost. Mine started having problems at that rate of boost and finally blew up even with #'s under 10.5 on the AFR. Mine now can go to 12# but I need race fuel even with the 0 compression wiseco pistons 9 #'s is awesome. As far as the 8DN vs the stock belt I had no problems at under 6#'s of boost but after the rebuild and cranking it to 7 and 9 on the switch I started blowing belts at under 200 miles. I went through 3 in 2 weekends so I am changing mine over next weekend. I finally got it back after being in the shop for 3 months for failed handwarmers, and no lights on the gauge pod.

Any chance the steam went in your air intake and leaned it out for just a second and detonated? MPI that were demos had intake outside of hood.

 

[NOS-PRO]

I will take a picture of my clutches now

8DN working great!

The belt is riding at the top now

 

[Yamadog]

Any chance the steam went in your air intake and leaned it out for just a second and detonated? MPI that were demos had intake outside of hood.

There is a chance that the planet temporarily lost atmosphere and the lack of oxygen caused it. It was dropping cylinders from mile 200 at 3.5 #'s of boost. and the first time was on the TY ride in Houghton, we were on the long and twisty trail 13 from Twin Lakes to Greenland at Pats Yamaha. I was no where near 3/4 throttle I am just not a fan of the CAT puter and no there was no ingestion of snow on the flat trails. The other 3 times prior to letting go it dropped cylinder or 2 and then after cooling down for an hour was running fine. The day she let go was riding alone out of Hurley at 8 am on a 15 deg morning clear skies went 6 miles and then just stopped. left it sit for an hour rode back limping and got to trailer and that was it. I would really be mad if they told me it is a snowmobile that cannot be ridden on the snow due to fear of ingestion!!!!

 

[TD Max]

I will take a picture of my clutches now

8DN working great!

The belt is riding at the top now

I take it you had the sheaves machined?

Both clutches?

Or is the low rolling resistance /strong grip of the asphalt setup contributing?

 

[stingray719]

There is a chance that the planet temporarily lost atmosphere and the lack of oxygen caused it. It was dropping cylinders from mile 200 at 3.5 #'s of boost. and the first time was on the TY ride in Houghton, we were on the long and twisty trail 13 from Twin Lakes to Greenland at Pats Yamaha. I was no where near 3/4 throttle I am just not a fan of the CAT puter and no there was no ingestion of snow on the flat trails. The other 3 times prior to letting go it dropped cylinder or 2 and then after cooling down for an hour was running fine. The day she let go was riding alone out of Hurley at 8 am on a 15 deg morning clear skies went 6 miles and then just stopped. left it sit for an hour rode back limping and got to trailer and that was it. I would really be mad if they told me it is a snowmobile that cannot be ridden on the snow due to fear of ingestion!!!!

"The other 3 times prior to letting go it dropped cylinder or 2 and then after cooling down for an hour was running fine" in my opinion shows early warning of head gasket issue, surprised your dealer did not catch that. My question though was shortly before the first time it happened did you have any steam from snow on radiator being blown into engine compartment? Not trying to open old wounds just trying to understand something.

 

[Yamadog]

"The other 3 times prior to letting go it dropped cylinder or 2 and then after cooling down for an hour was running fine" in my opinion shows early warning of head gasket issue, surprised your dealer did not catch that. My question though was shortly before the first time it happened did you have any steam from snow on radiator being blown into engine compartment? Not trying to open old wounds just trying to understand something.

No there was no ingestion of snow. I only ran the sled 3 times prior on sunny days and riding alone during break in. I spoke to my dealer, Hauck who did the turbo install and Matt at MPI all 3 said HMM? and said its running fine now? I said yes well good luck let us know if anything else happens. The 3rd time it even blew 1 qt of oil out of it and I was told that was a common problem cause of the ball valve freazing in the pressure relief line, which I said no way that day it was 34 deg F and drizzling. YamahaTim was with me on all but the 3 and then the final detonation and there was no warning or change in the AFR #'s

 

[Studroes144]

Please stop all this madness you guys are scaring me lol I think all the turbo guys with great luck should post me some encouraging words

 

[stingray719]

No there was no ingestion of snow. I only ran the sled 3 times prior on sunny days and riding alone during break in. I spoke to my dealer, Hauck who did the turbo install and Matt at MPI all 3 said HMM? and said its running fine now? I said yes well good luck let us know if anything else happens. The 3rd time it even blew 1 qt of oil out of it and I was told that was a common problem cause of the ball valve freazing in the pressure relief line, which I said no way that day it was 34 deg F and drizzling. YamahaTim was with me on all but the 3 and then the final detonation and there was no warning or change in the AFR #'s

Ok, I guess sometimes odd things happen. Sorry you had to go through it.

 

[stingray719]

Please stop all this madness you guys are scaring me lol I think all the turbo guys with great luck should post me some encouraging words

I would think 2 isssues on a first year setup beats the heck out of the you know who sled company that has countless engines fail I was just trying to figure out if his failure was just one of those things or steam related. As it is not steam related I will sit back down and be quiet now.

 

[TD Max]

There is a chance that the planet temporarily lost atmosphere and the lack of oxygen caused it. It was dropping cylinders from mile 200 at 3.5 #'s of boost. and the first time was on the TY ride in Houghton, we were on the long and twisty trail 13 from Twin Lakes to Greenland at Pats Yamaha. I was no where near 3/4 throttle I am just not a fan of the CAT puter and no there was no ingestion of snow on the flat trails. The other 3 times prior to letting go it dropped cylinder or 2 and then after cooling down for an hour was running fine. The day she let go was riding alone out of Hurley at 8 am on a 15 deg morning clear skies went 6 miles and then just stopped. left it sit for an hour rode back limping and got to trailer and that was it. I would really be mad if they told me it is a snowmobile that cannot be ridden on the snow due to fear of ingestion!!!!

Not wanting to rub salt in wounds either but:

The conditions eluded to would cause it to run excessively rich and possibly foul plugs not lean and burn down. Part throttle is where a lot of 2 strokes burn down and could easily happen to a 4 stroke as well.

"Dropping cylinders" should be an immediate red flag alerting to something being wrong. Many 2 strokes burn down/detonate at part throttle and I'm sure a 4 stroke could as well.

No there was no ingestion of snow. I only ran the sled 3 times prior on sunny days and riding alone during break in. I spoke to my dealer, Hauck who did the turbo install and Matt at MPI all 3 said HMM? and said its running fine now? I said yes well good luck let us know if anything else happens. The 3rd time it even blew 1 qt of oil out of it and I was told that was a common problem cause of the ball valve freazing in the pressure relief line, which I said no way that day it was 34 deg F and drizzling. YamahaTim was with me on all but the 3 and then the final detonation and there was no warning or change in the AFR #'s

34°f and drizzling are perfect conditions for icing in the intake and who knows where else.

A bit of "steam" (within reason) from snow melt would act more like a crude form of water injection which is used to reduce detonation.

Didn't Yamaha Tim say something about the two of you having bad experiences with errant A/F meters that you purchased?

My guess is either fuel quality/supply issue or just a lemon in general.

 

[Yamadog]

Ok, I guess sometimes odd things happen. Sorry you had to go through it.

Well thank you, I am not trying to scare anyone I love the turbo and mine had a problem from day 1! The dealers did not believe me or recognize what I was telling them would lead to catastrophic failure - BUT - Since i rebuilt on my own dime (no warranty) and added carillo rods and wiseco 0 compression pistions new waste gate and boost switch and took her up to 12# capability it is awesome!!! At launch on 9#'s it pulls the skis 12" out to 40 then they start to go to the sky at 60 ish they are 2' or more up and it carries them to well over 90 then slowly sets down mid 90's to 100 depending on the snow. Flip the switch back to 7#'s and there is still nothing I have run into out in the UP that will pull it except 1 heavily modded Apex XTX at over 15#'s of boost and other motor work. I have even run 2 Cat turbos with reflash and pulled them. The last ride of the season I ran into a CAT dealer from Chicago on one and made arrangements to run him on his way to meet me he blew up.

 

[Yamadog]

Not wanting to rub salt in wounds either but:

The conditions eluded to would cause it to run excessively rich and possibly foul plugs not lean and burn down. Part throttle is where a lot of 2 strokes burn down and could easily happen to a 4 stroke as well.

"Dropping cylinders" should be an immediate red flag alerting to something being wrong. Many 2 strokes burn down/detonate at part throttle and I'm sure a 4 stroke could as well.





34°f and drizzling are perfect conditions for icing in the intake and who knows where else.

A bit of "steam" (within reason) from snow melt would act more like a crude form of water injection which is used to reduce detonation.

Didn't Yamaha Tim say something about the two of you having bad experiences with errant A/F meters that you purchased?

My guess is either fuel quality/supply issue or just a lemon in general.

Well its all conjecture now and not worth looking back on it. He (tim) had the bad AFR and so did TOM (Mrsled) mine is AEM and has never been a problem.