Valve check?

[savageman69]

are there any aftermarket valves to install if we find these to be the issue?

 

[Allan]

The first time my valves tightened up at 15,000 miles my cost to replace the the cylinder head was shared with Arctic Cat. Is was decided to replace the whole cylinder head because the root cause had not been found but it was assumed to be a defective part. The second time at 24,000 miles I paid the bill for valve adjustment and inspection.

So u got 15000 miles the first time b 4 u had a problem, but only 9000 the next time even with cylinder head replaced. When they replaced the cylinder head did they put new valves in?
If so you would think u would of got close to the 15000 miles again before a problem.

 

[Mike P]

I agree. And till we all confirm whether we in fact have tight valves not much can be assumed. I believe they varied right from factory or shortly after. Probably will never prove that but it sure makes sense to me. Now if that's not the case it's really a issue because then it's either a defect or dirt causing it. Both will not be cured by just a adjustment. They will go tight again. I plan to take the dive in this weekend if I can stay away from all the snow coming in next few days!

I would ride now. Work on it later.

 

[FrozenTows4]

Tight valves could be part of the cold start issues that some are having. The spinning, sputtering, shot gun blast, and no start.
Even after replacing all relays, mine will not start colder than -10f. Warming up the new relays does not help. Warm up the engine to -8f and it will start. But after about 30 seconds, will drop to a very low idle to the point of just about dying.
The last couple of rides, even in warm weather if I didn't let it warm up to at least 165f, it would rev but die when returning to idle. After first initial 165f run, it's good for the day.
Strange, but it sure sounds like the early stages of tightening valves at 6100 miles.

 

[Allan]

I checked the part # s from a 2014 nytro and 2014 viper. all the part #'s related to the to heads and valves are the same.

So why no Nytro's with the problem.
Is it fuel? The nytro called for 91 octane and the viper 87.

 

[DTJ]

Just for reference, I have only run 91 non-oxygenated both before and after the turbo install.

 

[cobrajet ltx dx]

The relay issue’s are not causing hard starts. They only caused certain components to not operate when they froze in severe climates hence fuel pump operation reverse operation and ics operation.
I’m not ruling out tight valves causing issues but that is not the end all be all FIX.
These sleds at least mine from new NEVER STARTED like a 4 stroke should in cold weather and especially in up north severe cold.
With every ecu mapping change Yamaha did it got worse.
I could always smell the over fueling in the exhaust track and especially when the muffler would explode.
Agree or disagree.... there is more to this saga then just TIGHT VALVES.

 

[cobrajet ltx dx]

On the plus side the “cafe” standards are getting all redone with the automakers since the ridiculous standards set before are now changing.
Hope this makes it way to the power sports world.

 

[cobrajet ltx dx]

I checked the part # s from a 2014 nytro and 2014 viper. all the part #'s related to the to heads and valves are the same.

So why no Nytro's with the problem.
Is it fuel? The nytro called for 91 octane and the viper 87.

The way ecu mapping is today, if it mapped for 87 then the higher octane use actually is worse. To different burn rates. If you CUSTOM TUNE IT then higher octane is good but the oem mapping won’t adjust for the better.

 

[cannondale27]

The relay issue’s are not causing hard starts. They only caused certain components to not operate when they froze in severe climates hence fuel pump operation reverse operation and ics operation.
I’m not ruling out tight valves causing issues but that is not the end all be all FIX.
These sleds at least mine from new NEVER STARTED like a 4 stroke should in cold weather and especially in up north severe cold.
With every ecu mapping change Yamaha did it got worse.
I could always smell the over fueling in the exhaust track and especially when the muffler would explode.
Agree or disagree.... there is more to this saga then just TIGHT VALVES.

Right. But it could explain why some ran more crappy than others. Was another thread way back where some had throttle body’s out of sync too. It all can add up.

 

[DVW]

So u got 15000 miles the first time b 4 u had a problem, but only 9000 the next time even with cylinder head replaced. When they replaced the cylinder head did they put new valves in?
If so you would think u would of got close to the 15000 miles again before a problem.

The first time they addressed the tight valve issue they assembled a complete cylinder head from Yamaha parts in Arctic Cat service parts stock. Yamaha dealers might have access to a complete head assembly but Arctic Cat dealers did not. During the head assembly the valves where adjusted to fall within a acceptable range (the spec). It is probable that valve clearance variation on the rebuild was greater then original variation do to shim availability. The factory head contained shim sizes not available in service parts. This variation could explain the variation in life. But then product life is difficult to predict.

 

[DVW]

“So why no Nytro's with the problem.
Is it fuel? The nytro called for 91 octane and the viper 87” (quote from previous reply).

Allan
Good question. I can tell you that whenever possible I used 87 octane.

 

[cobrajet ltx dx]

Right. But it could explain why some ran more crappy than others. Was another thread way back where some had throttle body’s out of sync too. It all can add up.

Absolutely it all can add up.
All I can say with my issues is once I got it started and the temp light went out it always ran like a SWISS WATCH
Always pulled rpm, and had no drivability concerns.
My last trip was 2k with a blown muffler the entire time and it ran its #*$&@ OFF accept for my RT foot getting real hot lol

 

[STAIN]

I do know of a few Apexs that the valves got tight in at @12000 miles.
Are the valves stretching, the valve faces wearing or the valve seats pounding out?

 

[hognit09]

I checked the part # s from a 2014 nytro and 2014 viper. all the part #'s related to the to heads and valves are the same.

So why no Nytro's with the problem.
Is it fuel? The nytro called for 91 octane and the viper 87.

I had a nytro for 8 years and it called for 87 octane,not 91