03 Viper clutching issue

[pls93]

Hello Yamaha fans. Just joined and first post. “Hope I’m posting in the correct area”

This is the first sled I've owned and new to repair and adjustments on them.

I just picked up 03 viper mt this past spring. It sat for the last 5 years without running so I cleaned the carbs and did some other maintenance before I rode it. Sled runs good except it seems like it slips the drive belt or something. It does not always do it but happened about 5 times in a hour time span. It only happens from a dead stop and about half throttle it goes a bit but "thump thump thump" and smell a little rubber burning. once it gets past a certain RMP them it goes like normal. The belt is in good shape and has the same amount of play as our other viper does. The only thing I can think of is cleaning the primary with carb cleaner "I think it's the pulley in the front of the sled"?

Oh the sled is stock except for SLP pipes. When it was installed they did not add weights or springs to the clutch.

Any help would be appreciated.

thank you

 

[karlburns]

When you did your maintenance. Did you check all the bearings and make sure they were good? If you grab the clutch does it move at all if you try to wiggle it side to side? Also did you check your rollers to make sure there was no flat spots? All very basic stuff but need to know how much you did during your maintenance.

 

[pls93]

Sorry I did not do the maintenance but a shop did. They cleaned and re jetted the carbs for the pipes, inspected track, clutch, ect, replaced hyfax and they did not mention anything was wrong. Also I asked if weights or anything else should have been done to the clutch since it had SLP's and they said ride it and see if you like it or not. Visually I did check the play on the clutch and there was none, I did not check the rollers for flat spots, to be honest I'm not sure where the rollers are?

 

[Backwoods M Max]

What belt are you running? The 8dn is incredibly hard and slips anyways. If it was old from sitting from 5 years and hardened that may very well be the source of your problems. Try an ultimax xs-805, they grip better and don't generate as much heat In the clutches.

 

[pls93]

Also I noticed on the primary the belt at one time was riding really high on the pulley because it was very shiny. I looked on our other Viper and the belt didn't even go half way, the pulley was still dirty.

 

[pls93]

Thats a good question, I'm not sure whats on there. I got the sled from an older couple that bought it new and who knows if it was ever replaced. I know the spare belt looks really old.

 

[roudyroy1]

Maybe it's glazed. Throw new oem one on and try

 

[pls93]

Yeah I will do that. Thinking about it now It didn't start doing it until it got warm, tried to replicate it cold and it wouldn't slip.

 

[A couple of bucks]

"thump thump thump" and smell a little rubber burning.

Check track tension.

 

[karlburns]

Agree with the track tension and replacing the belt. If you took it to a shop I'd assume they checked tension but who knows with an answer of ride it see if you like it. It might be just a crap belt that your spending forever looking for a bigger problem.

To check the rollers when your looking at the primary you'll notice there's three arms that stick out away from the motor toward the front of the clutch ( part closest to you standing next to the machine). You'll see on those arms a couple silver round pieces that are kind of hidden by the arms. They just roll right there hence the name but can get flat. Takes 2 minutes to check them.

 

[mod-it]

I also thought of the track ratcheting when I read this. Ratcheting is when the track is too loose and the drivers skip on the track. I like to adjust one turn at a time until it stops, and actually don't mind if it gives one ratchet every once in a while when I load it hard.
As far as them piping it and not changing the clutching...wow, that isn't going to have you in the sweet spot for peak rpm's. With SLP's you're looking for it to hold 8900 rpm at WOT.

 

[karlburns]

As far as them piping it and not changing the clutching...wow, that isn't going to have you in the sweet spot for peak rpm's. With SLP's you're looking for it to hold 8900 rpm at WOT.

Exactly. Ride it see if you like it. Terrible answer. They run real good with all gas and no oil for a few miles as well..... Ignore the red light it's just the awesome indicator.

Just put of curiosity was this a dealership or what type of shop was it?

 

[pls93]

Check track tension.

The thumping did feel like it was more under the sled rather than front of the motor, still getting use to these things and they are alot of fun.

thanks

 

[pls93]

Agree with the track tension and replacing the belt. If you took it to a shop I'd assume they checked tension but who knows with an answer of ride it see if you like it. It might be just a crap belt that your spending forever looking for a bigger problem.

To check the rollers when your looking at the primary you'll notice there's three arms that stick out away from the motor toward the front of the clutch ( part closest to you standing next to the machine). You'll see on those arms a couple silver round pieces that are kind of hidden by the arms. They just roll right there hence the name but can get flat. Takes 2 minutes to check them.

Thank you for this, I will check them out next weekend. I will also be taking it back to the shop to have them adjust the track. guess I should have them check the other sled also.

 

[pls93]

Exactly. Ride it see if you like it. Terrible answer. They run real good with all gas and no oil for a few miles as well..... Ignore the red light it's just the awesome indicator.

Just put of curiosity was this a dealership or what type of shop was it?

I can just put a sticker over that light, just a suggestion anyway right lol.

As for the shop they work on quads, dirt bikes snowmobiles ect. They are good at what they do but maybe not very knowledgeable on aftermarkets items.

 

[pls93]

I also thought of the track ratcheting when I read this. Ratcheting is when the track is too loose and the drivers skip on the track. I like to adjust one turn at a time until it stops, and actually don't mind if it gives one ratchet every once in a while when I load it hard.
As far as them piping it and not changing the clutching...wow, that isn't going to have you in the sweet spot for peak rpm's. With SLP's you're looking for it to hold 8900 rpm at WOT.

I'm good with wrenching but since I travel so much and these were used I just wanted to send to the shop for a baseline and do my own maintenance from now on. I will need to read up on adjusting so I don't have to rely on the shop.

As for the pipes I will read up on what is recommended for the SLP's. When you say 8900 WOT does that mean I have to try different springs to achieve that or is the kit going to be correct?

thanks for your help

thanks for all the help

 

[karlburns]

Adjusting the track is nothing if you look it up on YouTube it's very simple. All you gotta do is raise the rear end and grab a couple wrenches. Just gotta make sure you adjust them to the same on both sides.

8900 is your ideal RPM you'll need to see what your currently hitting wide open for us to give you some advice on that. I'll be honest I'm not great at clutches so those questions I'd leave to some of these other guys.

 

[A couple of bucks]

Adjusting track.

1. Suspend rear of sled from ceiling. Or make for dern sure it is not going to fall off/over of the jack stands.
2. Back off the jam nut at the rear axle that adjusts axle tension.(right through the track windows)
3. Turn adjusters so that the track tightens up to where your happy. Start sled and goose the throttle a few times really good. Look at the track from the rear and insure that it is tracking evenly on both the left and the right slider. Make minor adjustment to achieve this. Repeat procedure #3 as many times as it take to where it is tracking straigh and even.
4. Re-tighten the jam nuts

 

[A couple of bucks]

Too bad all the rain out your way isn't snow.

 

[pls93]

Adjusting track.

1. Suspend rear of sled from ceiling. Or make for dern sure it is not going to fall off/over of the jack stands.
2. Back off the jam nut at the rear axle that adjusts axle tension.(right through the track windows)
3. Turn adjusters so that the track tightens up to where your happy. Start sled and goose the throttle a few times really good. Look at the track from the rear and insure that it is tracking evenly on both the left and the right slider. Make minor adjustment to achieve this. Repeat procedure #3 as many times as it take to where it is tracking straigh and even.
4. Re-tighten the jam nuts

Sounds easy enough, I will let you know how it comes out.