I need help SW down again losing coolant 550 miles - *FIXED* fingers crossed

[kinger]

The head warped from the constant overheat? It seems hard to believe the head was warped from day one. Was this motor apart BEFORE the problems occurred? Was the second problem an install error with your ARP head studs? Who installed the head studs?
I may not be following correctly but did the first head have a crack from the factory and the second head never seal properly?

First motor was a crack in the cylinder head, a defect from the Chinese sourced head.

This was the second motor where Yamaha makes you buy every single part and the dealer has to assemble it. While they were assembling it I asked them to put in ARP head studs to get it ready for some big boost eventually. The middle cylinders never sealed up there were no lines on the head gasket I looked at it myself. They wanted to go back to stock talk to yield bolts I will keep/sell the ARP.

When the motor overheated it was for such a short amount of time I doubt it could’ve warped anything.

 

[Big_Phil]

The head warped from the constant overheat? It seems hard to believe the head was warped from day one. Was this motor apart BEFORE the problems occurred? Was the second problem an install error with your ARP head studs? Who installed the head studs?
I may not be following correctly but did the first head have a crack from the factory and the second head never seal properly?

These engines have to get pretty hot to warp a head. I bought a Nytro back in the day that got so hot it melted the wire to the oil pressure sensor and melted the coils into the head. The head was only out 7 thou.

 

[bleedyamaha]

WTH. Kinger you come on here and don’t talk about your trip. We want details.

 

[kinger]

Well, how was that 850?

The best word to describe the sled was fun and playful! 290 miles total and was flawless!

Motor: wow I didn’t know two strokes could be this snappy and punchy. It was an arm stretcher close to the likes of my boosted Apex from 20 mph to 60 mph! I was more shocked at the response and the new clutch they have in the 2020s. It was instant, and I mean instant. It was so fun to drive through tight twisty turns and jumping small hills in the trail. I don’t know how you make a two-stroke better. I rode a new 800 Polaris assault and it wasn’t even in the same league.

chassis - it was narrow, cold, and the seat was barely a seat. After 150 miles on one day my rear end hurt a little bit. The fit and finish of the panels was really spot on I liked how they allow access to the front of the sled.

suspension - for an out of the box Suspension I could not get it to bottom out and I tried really hard and this is really rare for me, normally I can get anything to reach its limits. Everything was soft, I played with the KYB shocks throughout their entire adjustment ranges, the transfer blocks , everything but the limiter strap and I couldn’t quite dial in the perfect setting but there were plenty of settings where it didn’t matter it just worked. The window of operation is so large that there was never a bad setting and there were never any harsh bumps. I also found a nice stretch of moguls and when you lean back on the seat and give it some gas it soaked them up pretty darn good for a stock suspension. My ZX2 is better at this and also had better transfer but again for an out-of-the-box suspension I wouldn’t change this out. I found lots of large jumps and the sled flies through the air very nicely and again lands soft. Overall it was very confidence inspiring you could literally ride it to its limit without even trying. There was plenty of times when I had it at wide open throttle and at no time did I feel like I was out of control.

Overall- this sled was just pure fun. It flat works in any condition and it may make me a Doo fan someday. That said it doesn’t have the sheer power and adrenaline rush of a boosted Yamaha. I have so little miles on my side winder, but the miles I did have I felt like the handling wasn’t a problem. My BTX is also a lot more of a handful in the trails by design and something I prefer over this 137 inch XRS with a wide stance, the XRS I could easily drive faster than my BTX. The 850 is just confidence inspiring though, you never feel out of control like you can feel on a 300hp Yamaha at certain periods of time. I can see why they are the number one brand in the industry right now. If I wanted a sled where I didn’t want to make a single modification to it and rode it as is and have fun this would be my number one choice!

back home at the dealer they showed me an 850 that was brought in and I got to look at the crank bearings and the crankshaft and they are built very very well compared to the old Doo 800s that I remember my friends blowing up. I will be interested to see how many miles these engines go before needing a rebuild.

Yamaha.....please get your head in the game!

 

[RAMSOMAIR]

hmmmmm, why was the 850 engine apart???

 

[STAIN]

First motor was a crack in the cylinder head, a defect from the Chinese sourced head.

This was the second motor where Yamaha makes you buy every single part and the dealer has to assemble it. While they were assembling it I asked them to put in ARP head studs to get it ready for some big boost eventually. The middle cylinders never sealed up there were no lines on the head gasket I looked at it myself. They wanted to go back to stock talk to yield bolts I will keep/sell the ARP.

When the motor overheated it was for such a short amount of time I doubt it could’ve warped anything.

So it sounds as if the first problem was a Yamaha problem and the second was an assembly problem, correct?

 

[cannondale27]

The best word to describe the sled was fun and playful! 290 miles total and was flawless!

Motor: wow I didn’t know two strokes could be this snappy and punchy. It was an arm stretcher close to the likes of my boosted Apex from 20 mph to 60 mph! I was more shocked at the response and the new clutch they have in the 2020s. It was instant, and I mean instant. It was so fun to drive through tight twisty turns and jumping small hills in the trail. I don’t know how you make a two-stroke better. I rode a new 800 Polaris assault and it wasn’t even in the same league.

chassis - it was narrow, cold, and the seat was barely a seat. After 150 miles on one day my rear end hurt a little bit. The fit and finish of the panels was really spot on I liked how they allow access to the front of the sled.

suspension - for an out of the box Suspension I could not get it to bottom out and I tried really hard and this is really rare for me, normally I can get anything to reach its limits. Everything was soft, I played with the KYB shocks throughout their entire adjustment ranges, the transfer blocks , everything but the limiter strap and I couldn’t quite dial in the perfect setting but there were plenty of settings where it didn’t matter it just worked. The window of operation is so large that there was never a bad setting and there were never any harsh bumps. I also found a nice stretch of moguls and when you lean back on the seat and give it some gas it soaked them up pretty darn good for a stock suspension. My ZX2 is better at this and also had better transfer but again for an out-of-the-box suspension I wouldn’t change this out. I found lots of large jumps and the sled flies through the air very nicely and again lands soft. Overall it was very confidence inspiring you could literally ride it to its limit without even trying. There was plenty of times when I had it at wide open throttle and at no time did I feel like I was out of control.

Overall- this sled was just pure fun. It flat works in any condition and it may make me a Doo fan someday. That said it doesn’t have the sheer power and adrenaline rush of a boosted Yamaha. I have so little miles on my side winder, but the miles I did have I felt like the handling wasn’t a problem. My BTX is also a lot more of a handful in the trails by design and something I prefer over this 137 inch XRS with a wide stance, the XRS I could easily drive faster than my BTX. The 850 is just confidence inspiring though, you never feel out of control like you can feel on a 300hp Yamaha at certain periods of time. I can see why they are the number one brand in the industry right now. If I wanted a sled where I didn’t want to make a single modification to it and rode it as is and have fun this would be my number one choice!

back home at the dealer they showed me an 850 that was brought in and I got to look at the crank bearings and the crankshaft and they are built very very well compared to the old Doo 800s that I remember my friends blowing up. I will be interested to see how many miles these engines go before needing a rebuild.

Yamaha.....please get your head in the game!

How hot were the clutches and what about fuel range?

 

[kinger]

So it sounds as if the first problem was a Yamaha problem and the second was an assembly problem, correct?

Possibly assembly but they didn’t check the flatness of the brand new head or block. Both are being checked this week. Should have it back next week.

 

[kinger]

hmmmmm, why was the 850 engine apart???

Crazy it split in half! Still ran on one cyl! It was a bad (defect) casting, had low miles like 550.

 

[kinger]

How hot were the clutches and what about fuel range?

It was in break in and i was getting 12 mpg according to the dash. They say it will get near 20 when broke in. I was riding it aggressively. Clutches I checked once and were warm but not hot. There was more belt dust then I was expecting. I am used to the 8DN which as you know dusts very little.

 

[Big_Phil]

It was in break in and i was getting 12 mpg according to the dash. They say it will get near 20 when broke in. I was riding it aggressively. Clutches I checked once and were warm but not hot. There was more belt dust then I was expecting. I am used to the 8DN which as you know dusts very little.

Etecs only get good fuel mileage when you drive them easy. They run a super lean mixture at idle and cruise. Something like 25-1.

 

[Turboflash]

Possibly assembly but they didn’t check the flatness of the brand new head or block. Both are being checked this week. Should have it back next week.

Critical, costly, and rookie mistake at dealer NOT checking flatness of head and block. These are elementary and basic engine-building elements that can never be over-looked. IMO, too many dealers/shops don't have true professional engine builders.

It's why I fixed my cracked head myself (even though sled was under warranty) because then I KNOW FOR SURE it's done right. While visiting my dealer about 1 month ago, they had a 998 head off for repair and it only confirmed I would never let them work on my sled. Kids that butcher and cobble. I know there are some capable dealers/shops too.
IF head and block are flat, and are professionally installed with ARP head stud kit, the 998 will never "use" even a drop of coolant, ever. Prior to installing a new head and studs, my 280HP 998 used to "use" some coolant over a few weekends. Sent oil sample in for analysis = coolant in oil! Installed new head w ARP head studs, changed to 320 tune, never uses any coolant ever. Head is sealed.

 

[ClutchMaster]

Critical, costly, and rookie mistake at dealer NOT checking flatness of head and block. These are elementary and basic engine-building elements that can never be over-looked. IMO, too many dealers/shops don't have true professional engine builders.

It's why I fixed my cracked head myself (even though sled was under warranty) because then I KNOW FOR SURE it's done right. While visiting my dealer about 1 month ago, they had a 998 head off for repair and it only confirmed I would never let them work on my sled. Kids that butcher and cobble. I know there are some capable dealers/shops too.
IF head and block are flat, and are professionally installed with ARP head stud kit, the 998 will never "use" even a drop of coolant, ever. Prior to installing a new head and studs, my 280HP 998 used to "use" some coolant over a few weekends. Sent oil sample in for analysis = coolant in oil! Installed new head w ARP head studs, changed to 320 tune, never uses any coolant ever. Head is sealed.

Amen! I have been in my local dealers shop....
Looks like a high school auto shop! Parts and tools layin everywhere.....everyone on their phones playing candy crush, that $hit.

 

[kinger]

Critical, costly, and rookie mistake at dealer NOT checking flatness of head and block. These are elementary and basic engine-building elements that can never be over-looked. IMO, too many dealers/shops don't have true professional engine builders.

It's why I fixed my cracked head myself (even though sled was under warranty) because then I KNOW FOR SURE it's done right. While visiting my dealer about 1 month ago, they had a 998 head off for repair and it only confirmed I would never let them work on my sled. Kids that butcher and cobble. I know there are some capable dealers/shops too.
IF head and block are flat, and are professionally installed with ARP head stud kit, the 998 will never "use" even a drop of coolant, ever. Prior to installing a new head and studs, my 280HP 998 used to "use" some coolant over a few weekends. Sent oil sample in for analysis = coolant in oil! Installed new head w ARP head studs, changed to 320 tune, never uses any coolant ever. Head is sealed.

I am going to have them do ARP following the factory sequence with first pass to 25ft-lbs, then 2nd pass 55 ft-lbs. I'm wondering if they defaulted to Factory tq spec of 18 ft-lbs and 270 degrees after the first time, then I can see the head not being sealed by the ARP studs.

 

[Turboflash]

I am going to have them do ARP following the factory sequence with first pass to 25ft-lbs, then 2nd pass 55 ft-lbs. I'm wondering if they defaulted to Factory tq spec of 18 ft-lbs and 270 degrees after the first time, then I can see the head not being sealed by the ARP studs.

Kinger, official torque specs for ARP are: 1st pass @ 12 ft.lbs. 2nd pass @ 25 ft.lbs. 3rd pass @ 55 ft.lbs all following Yamaha sequence.