LJ 452
TY 4 Stroke God
O.K. well finally got my Nytro back from the dealer for some issues I knew about. Now it’s time to go through it and see what’s what.
Pull the skid and immediately notice the front arm is able to shift side to side, about 1.5 to 2 inches. This probably occurred during the later third of the season as I remove my skid and inspect at least twice during a season usually three to four times. At any rate I figure the bushings/bearings are toast, wrong, the needle bearings are in great condition, the issue turns out to be the eyelets in the arm itself have egged out. This is one of the few fasteners I have not touched, checking the torque on these may prevent slipping however I don’t think you’re going to win that race. So I decided that the contact area needs to be increased. What I did was weld coins on each side of the arm (4 total) they were about a 6mm thick and should greatly help the wear in this area. One thing to note, the torsion spring will be very close to the bolt with the now thicker flange, I have not completed the assembly but interference needs to be considered. In the end, either a dome head bolt may be needed, or a bit of material may need to be removed.
The front bolt pivots in the front arm were also worn a bit, nothing too crazy however I decided I would replace them. Originally I thought I would get some oilite and use that. I couldn’t find any stock (local hardware) that would work with or without machining. So I thought what the heck I’ll just buy the stock bushings and be done with it. Well, at $22.00+ a piece, and needing 4 of them; I think I’m going to be changing the steel sleeve inside and doing my own oilites that will work. What a total rip off.
As I had mentioned in other posts, the rear arm had began cracking last year (3,000 miles total) and I had to weld that up. No warranty on that, go figure. I would say that if it were to fail completely while riding, it could get real interesting, so I will also be adding a strap that will be welded to the top of each down tube and wrap around the pivot, and then welded to the bottom of the down tube. Originally I was going to increase the diameter of the pivot itself, but time has got me again, maybe next year.
Since I didn’t have time to deal with the top secret shock work, also known as getting specs and seals for the rears, I decided to send them off to Hygear. I knew it would be pricey, but I also knew I would get what I paid for. I should note that I was also concerned about the restrictive reservoir hose on the center shock. See Hygears site for info on that. The shocks go to Hygear and I get a call a few days later, planned on going over the setup I was looking for and got a different surprise. They tell me that the center shock shaft is toast. The shaft had damage at the seal head and the chrome and shaft had surface damage. SURPRISE you need a new shaft, and I’ll tell you that they are NOT cheap, remember it’s the package with compression and rebound adjustability. My guess is that the worn front arm was likely the root cause of the damage. The bottom of the skid could shift side to side and misalign the shock causing a side load on the shaft. I will be getting the old shaft back and will post pics. Aside from that will the shocks should be good.
The tunnel, well the steel drop brackets that the rear skid bolts through are showing cracks. The cracks are actually propagating from the spot welds on each side of the bolt hole. At first I figured it was from flexing, but I’m begining to think it may be caused from the ice. Because both sheets would bend on the same plane and at the same time, cracks should not form. I think what may be happening is that moisture is getting between the plates, when the moisture freezes; it expands and loads the spot weld tension rather than shear. Were is this crazy moisture coming from well it's the same stuff that coats your tunnel from the inside. the exhaust may or may not be at fault here, more than likely it is. The ice expansion creates a peeling effect and the crack forms. Again, I’ll try to get pics but it may not be clear enough to see. I have also noticed that the grip sections on the tunnel are getting stress cracks right in the trough of the serrations. Seems to me the RTX S.E. could have used the tunnel stiffeners from the factory.
One of the things that warranty was kind enough to cover was the radiator support brackets. Both the left and right-hand were cracked and needed to be replaced. If you pull the hood off and look you’ll see a hairline crack were the bracket meet the chassis, just above the bolt. Both of them failed the same way, so I would think it’s simply a durability thing.
Just a few major issues to watch for as you go over your sleds whether it is pre-season, or pre-trip. Obviously I should have checked all of this out before going to the dealer, again time and the appearance of everything appearing ok got the best of me. I should have known I wasn't going to be that lucky. I'm going to be talking with the dealer once the parts are returned and see what's what, I have zero confidence in anything being covered and don't expect a thing to be done about it. So, I shouldn't be disappointed.
The Love/Hate relationship with the Nytro continues.
Pull the skid and immediately notice the front arm is able to shift side to side, about 1.5 to 2 inches. This probably occurred during the later third of the season as I remove my skid and inspect at least twice during a season usually three to four times. At any rate I figure the bushings/bearings are toast, wrong, the needle bearings are in great condition, the issue turns out to be the eyelets in the arm itself have egged out. This is one of the few fasteners I have not touched, checking the torque on these may prevent slipping however I don’t think you’re going to win that race. So I decided that the contact area needs to be increased. What I did was weld coins on each side of the arm (4 total) they were about a 6mm thick and should greatly help the wear in this area. One thing to note, the torsion spring will be very close to the bolt with the now thicker flange, I have not completed the assembly but interference needs to be considered. In the end, either a dome head bolt may be needed, or a bit of material may need to be removed.
The front bolt pivots in the front arm were also worn a bit, nothing too crazy however I decided I would replace them. Originally I thought I would get some oilite and use that. I couldn’t find any stock (local hardware) that would work with or without machining. So I thought what the heck I’ll just buy the stock bushings and be done with it. Well, at $22.00+ a piece, and needing 4 of them; I think I’m going to be changing the steel sleeve inside and doing my own oilites that will work. What a total rip off.
As I had mentioned in other posts, the rear arm had began cracking last year (3,000 miles total) and I had to weld that up. No warranty on that, go figure. I would say that if it were to fail completely while riding, it could get real interesting, so I will also be adding a strap that will be welded to the top of each down tube and wrap around the pivot, and then welded to the bottom of the down tube. Originally I was going to increase the diameter of the pivot itself, but time has got me again, maybe next year.
Since I didn’t have time to deal with the top secret shock work, also known as getting specs and seals for the rears, I decided to send them off to Hygear. I knew it would be pricey, but I also knew I would get what I paid for. I should note that I was also concerned about the restrictive reservoir hose on the center shock. See Hygears site for info on that. The shocks go to Hygear and I get a call a few days later, planned on going over the setup I was looking for and got a different surprise. They tell me that the center shock shaft is toast. The shaft had damage at the seal head and the chrome and shaft had surface damage. SURPRISE you need a new shaft, and I’ll tell you that they are NOT cheap, remember it’s the package with compression and rebound adjustability. My guess is that the worn front arm was likely the root cause of the damage. The bottom of the skid could shift side to side and misalign the shock causing a side load on the shaft. I will be getting the old shaft back and will post pics. Aside from that will the shocks should be good.
The tunnel, well the steel drop brackets that the rear skid bolts through are showing cracks. The cracks are actually propagating from the spot welds on each side of the bolt hole. At first I figured it was from flexing, but I’m begining to think it may be caused from the ice. Because both sheets would bend on the same plane and at the same time, cracks should not form. I think what may be happening is that moisture is getting between the plates, when the moisture freezes; it expands and loads the spot weld tension rather than shear. Were is this crazy moisture coming from well it's the same stuff that coats your tunnel from the inside. the exhaust may or may not be at fault here, more than likely it is. The ice expansion creates a peeling effect and the crack forms. Again, I’ll try to get pics but it may not be clear enough to see. I have also noticed that the grip sections on the tunnel are getting stress cracks right in the trough of the serrations. Seems to me the RTX S.E. could have used the tunnel stiffeners from the factory.
One of the things that warranty was kind enough to cover was the radiator support brackets. Both the left and right-hand were cracked and needed to be replaced. If you pull the hood off and look you’ll see a hairline crack were the bracket meet the chassis, just above the bolt. Both of them failed the same way, so I would think it’s simply a durability thing.
Just a few major issues to watch for as you go over your sleds whether it is pre-season, or pre-trip. Obviously I should have checked all of this out before going to the dealer, again time and the appearance of everything appearing ok got the best of me. I should have known I wasn't going to be that lucky. I'm going to be talking with the dealer once the parts are returned and see what's what, I have zero confidence in anything being covered and don't expect a thing to be done about it. So, I shouldn't be disappointed.
The Love/Hate relationship with the Nytro continues.
mach9
TY 4 Stroke Master
Gees, man.
I'd like to see a photo or 2 of some of this stuff.
I'd like to see a photo or 2 of some of this stuff.
tapex_07
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Wow sounds like the sled has been used 
2008FxNytro
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mach9 said:
X2, with only 3k on it this should not be happening. i had over 8 on my 08 and rode the hell out of that thing and never had the drop brackets in the rear crack. did break the W arm but that was expected as i think any sled i have owned has broken eventually.
RTX Meirda
TY 4 Stroke Master
ditto
LJ 452
TY 4 Stroke God
I should clarify, the 3,000 mile mark was when the rear arm had began self destruction. Agree, I expect the suspension arms to fail at some point, just not sure it should have happened that early. The sled as it sits today has about 4,600 miles. I would guess the front arm failure (egged rear mounting tabs) to have occurred between 3,800 and 4,600 miles. The problem is that I think once it begins, it happens very quickly. I intend to post some pictures of the issues, I won't be able to show the egged holes as I have already repaired, but I will show the repair. Also I will try to get the other cracks posted.
For the record I don't feel I abuse my sled, if you were to look at it you would certainly not think it's abused. I do however not back down from the bumps, I don't ride out of control but certainly like to go though the bumps at a good pace. But, that's why I got the RTX S.E. right? This is supposed to be the ditch banging, big bump, baddest thing they make right? Oh well, live and learn.
All I can say is that you guys should pull the skids and check the slop in the front arm, if it gets too bad you may be out more than you think. You won't be able to tell with the skid in. Apparently I should be a durability tester for snowmobiles, it seems I find these weaknesses in about half the miles most do.
For the record I don't feel I abuse my sled, if you were to look at it you would certainly not think it's abused. I do however not back down from the bumps, I don't ride out of control but certainly like to go though the bumps at a good pace. But, that's why I got the RTX S.E. right? This is supposed to be the ditch banging, big bump, baddest thing they make right? Oh well, live and learn.
All I can say is that you guys should pull the skids and check the slop in the front arm, if it gets too bad you may be out more than you think. You won't be able to tell with the skid in. Apparently I should be a durability tester for snowmobiles, it seems I find these weaknesses in about half the miles most do.
Grimm
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LJ 452 said:
Well, for 2009, Yamaha advertised it as such, as it fell into their "Extreme Rough Trail" category. By the following year, Yamaha removed that category and classified it as a "Rough Trail" sled...demoted.
2008FxNytro
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LJ 452 said:
Now this slop was at the two mounting point ont he rail of the front W arm correct? ive got a brand new chassis this yr and usually check my bolts a couple two three times a yr to make sure all is tight and usually pull the skid once a year just to check it over and grease it. so ill have to keep an eye on it.
LJ 452
TY 4 Stroke God
dirkdiggler
Suspended
nice pics. I'll inspect mine next time I pull my skid.
ShootToThrill
VIP Member
I have a set of rear tunnel brackets for the SE. I can send you them for the shipping cost only. 12.00 2-3 day priority mail.
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