"The shift collar within the case slides back and the forward splines disengage. The vehicles that we have had happen to us never completely destroyed anything. Just messes up the spline engagement teeth enough to worry about. Since the Viper/7000s have cut steel top sprockets they are more resistant and can take some of this abuse. Usually they can pop out 3 to 4 times and you can get them back into forward. After that is questionable."
YamahaTim
Lifetime Member
- Joined
- Sep 21, 2013
- Messages
- 2,089
- Reaction score
- 95
- Points
- 493
- Location
- Farmington, MN
- Country
- USA
- Snowmobile
- 2014 Yamaha Viper LTX SE MPI Turbo
So what your saying is that it's messed up... 
Apex I agree that is exactly what happens. But my question is why is it happening now and not last year after the rack update Cat did? Something changed. So far only change I can see that would cause a worm drive servo to lose position is the Servo itself or a errant signal. Doing more than one "fix" at a time such as a reflash and this detent makes no sense.
http://mechteacher.com/worm-gear/
http://mechteacher.com/worm-gear/
Good point not sure on that but being that it a timed unit I'm guessing that is part of the problem. Maybe thats why a true yami has the mechanical reverse and polaris and skidoo reverse the engine.
Agree. Never has there been a perfect reverse system and electric reverse of which I can think of only 3. Two have not been ideal. Cat did seem to have the reverse right with the diamond drive and it did seem to be fixed on the updated cats. I sure dont feel like experimenting since I am putting way more miles on my sled than my truck now. Have a good night and ride,ride,ride!
YamahaTim
Lifetime Member
- Joined
- Sep 21, 2013
- Messages
- 2,089
- Reaction score
- 95
- Points
- 493
- Location
- Farmington, MN
- Country
- USA
- Snowmobile
- 2014 Yamaha Viper LTX SE MPI Turbo
I didn't mind the mechanical reverse. Was not that big of a deal, really how often do you use reverse anyway.
TurboJamie
TY 4 Stroke God
What boggles my mind is 3 years now and they are still tinkering with this chain case. The update does explain why my 12 cat kept jumping out of gear though. At least they seem to have a fix. I reverse 1 maybe 2x a day for me on my 1200 I flip the handle down and reverse its simple and reliable. I dont understand why everyone in society needs to push a button to back up. Even in mags they rag on manual reverse, last time I checked most cars still use...wait for it...a shifter!
TestMaster
Lifetime Member
- Joined
- Sep 28, 2013
- Messages
- 693
- Reaction score
- 297
- Points
- 1,078
- Location
- Alba, Michigan
- Website
- www.gdls.com
- Country
- USA
- Snowmobile
- 2014 SR Viper LTX SE
2014 SR Viper LTX DX
2001 Venture 600
Given to a friend - 1998 SRX 700s
Two stroke engines start in reverse
First commercial use was in the 50's when mercury marine eliminated the reverse gear from their upper power engines, making a faster "smaller" lower unit. Starter ran reverse direction for reverse. Lost favor cause luxury market didn't accept well because of time lag to enter reverse, they kept running into stuff cause they couldn't get into reverse fast enough. LOL. But true!
Four strokes don't start in reverse.
They need to change direction of power application through a mechanical method.
First commercial use was in the 50's when mercury marine eliminated the reverse gear from their upper power engines, making a faster "smaller" lower unit. Starter ran reverse direction for reverse. Lost favor cause luxury market didn't accept well because of time lag to enter reverse, they kept running into stuff cause they couldn't get into reverse fast enough. LOL. But true!
Four strokes don't start in reverse.
They need to change direction of power application through a mechanical method.
Well Yamaha did issue the bulletin same update Cat has. Guess its time to put my trust to the test because I dont like this fix.
awolb69
Extreme
I agree with you Cannondale on the "don't like this fix" part. My Viper now has 1,100 mi on it. Right at the beginning, my dealer asked me to bring it back in to check the positioning of the shift servo. I stood right there as they took it apart and as soon as they removed the 3 screws holding the motor to the chaincase, it spun itself to the 1 o'clock position with tension just as we were originally told they should be. THIS WAS HOW IT CAME FROM THE FACTORY. NEVER BEEN APART PRIOR TO THIS. They simply reinstalled the motor at the 1 o'clock position and then rotated it back to 12 and reinstalled the bolts. Not once to this day has my sled had any shifting or pop out of gear issues. And yes, I have put it in reverse under load several times.cannondale27 said:
TJ-R
Extreme
- Joined
- Jan 28, 2013
- Messages
- 94
- Reaction score
- 23
- Points
- 788
- Country
- USA
- Snowmobile
- 14 Viper XTX
cannondale27 said:
Yamaha bulletin 001 issued dated 1-24-14 yesterday, here is the link to it. http://www.ty4stroke.com/viewtopic.php? ... 44#1124644
stingray719
TY 4 Stroke God
awolb69 said:
I agree, and I will be following that same scenario when I reassemble ours. Or I could listen to apexgt....lol....
stingray719
TY 4 Stroke God
cannondale27 said:
I am curious why you don't like this? Take apart about any motorcycle engine/trans and you will see detents just like this keeping you bike in gear. Looks solid to me just curious why you don't like it?
This is only a guess because I have not gotten my hands on a servo to take apart but I will. I bet the worm gear is spring loaded at least one way. This would allow some tolerance. The bulletin does say to clock it to aid in assembly. Guys a CNC machine uses ball screws to move everything. Yes not same as servo but a motor can be controlled very precisely. Only reason any big tolerance would be needed is if the assembly isnt built to tolerance. Thats the mechanical aspect that would account for any of the issues. On the electrical side programing,bad connections or stray signals could account for it all. None of those have been addressed and with the amount of codes and weird starts I believe something is going on there. By doing the mechanical side they are avoiding EPA certification which will need to be done for any reflash. Are they just keeping us happy till then? We will find out soon I guess.
stingray719 said:
The case its riding in is very thin and not designed to have that in there. Also there have been servo motors that failed. Overcoming the detent will put more stress on the servo motor itself. As I said before the design of the system is good as is. Execution obviously needs some help. Also why so inconsistent everyone should be having the issues and many including me are not after countless reverse engagements. You dont add complexity to a problem. You fix the problem.
