Thatspec
Extreme
http://www.ty4stroke.com/viewtopic.php?t=22029
The mod involving lowering the suspension on an '03 Mt. by drilling higher holes in the mounting brackets specifically. I've been riding lowered now for several weeks in deep heavy snow, and while I love the handling difference, I had this vibration. Turns out its lack of clearance in the tunnel which makes sense as the vibration would go away on the trails. I didn't even drill my holes quite as high as the pics in the above thread.
When I raised it back up one hole last night, long story short, vibration gone in the deep but more importantly, I've got like 20% more power now in the deep. Going to do some extensive riding today to see if I can put up with the handling. I do have the MPI transfer kit installed, and set at neutral. Now I'll probably be able to trench again faster than ever ;^).
Has anyone else found this vibration/power loss or did I just do it wrong?
Thanks, Mark
The mod involving lowering the suspension on an '03 Mt. by drilling higher holes in the mounting brackets specifically. I've been riding lowered now for several weeks in deep heavy snow, and while I love the handling difference, I had this vibration. Turns out its lack of clearance in the tunnel which makes sense as the vibration would go away on the trails. I didn't even drill my holes quite as high as the pics in the above thread.
When I raised it back up one hole last night, long story short, vibration gone in the deep but more importantly, I've got like 20% more power now in the deep. Going to do some extensive riding today to see if I can put up with the handling. I do have the MPI transfer kit installed, and set at neutral. Now I'll probably be able to trench again faster than ever ;^).
Has anyone else found this vibration/power loss or did I just do it wrong?
Thanks, Mark
ViperTurboPete
TY 4 Stroke Master
- Joined
- Mar 25, 2005
- Messages
- 1,068
- Age
- 58
- Location
- Sudbury, Ontario
- Country
- Canada
- Snowmobile
- 2015 Viper XTX LE MPI Turbo
2022 Expedition Extreme 850
Is the vibration coming from too much snow being jammed up in the tunnel?? Or is the track touching the top of the tunnel? I am into alot of slush these days on the lakes and it makes me wonder about slush build up and clearance.
I want to try this mod in the worst way.
I want to try this mod in the worst way.
Thrusted Vector
Expert
Did you have the MPI transfer kit installed when you did the mod?Also how did you come up with the measurements if you didn't use prescribed distance.The Proaction Plus suspension is extremly sensitive being correct,if the meassurement aren't right,you could end up with the suspension binding and that could be causing the vibration.Was the Vibration there all the time or only when the suspension was compressed.I only ask these questions because I've done this mod to quiet a few machines and have never had this complaint.The nice thing about this mod is that it is reversible if you don't like it.
Thatspec
Extreme
Pete,
I'm making an assumption about the lack of clearance based on the vibration going away on hard pack. It has also gone completely now that I have reverted back to (what is now the center) bolt hole. The track was not touching in the tunnel, just closer than it would be in the upper bolt holes. Unfortunately I changed several things when I did this mod including loosening the track about three full turns of the adjusters, as well as changing to using only two inside rear idler wheels. Again though, I'm not feeling it anymore since I went to the center bolt hole in the rear bracket.
Rode for six hours today and only did about 20 miles in one steep clear cut, which should give a good indication as to how often I was digging out (I think I was burried 30% of the time). I could sink past my waist in new snow. We have been getting a bunch here in the NW (Mt. Hood) with the local ski area just breaking 400" so far this season, most of it very heavy. The machine felt more top heavy, and tended to trench more easily than in the mod setting, but it could have been the amount of new snow to some extent, every day is different. I'm going to see if I left enough room between the new hole, and the upper stock hole to drill an in between setting. That 3/4" really makes a big difference.
Maybe some of my other settings aren't quite right. What If I make the MPI transfer straps a little tighter so it doesn't open up as much? What about the front limiters? Searching provides plenty of conflicting info on that setting (I'm about in the middle).
Thanks for any info on your settings ('03 RX1 MT, stock skid)
On the plus side, it seems that I'm not using oil since I've been checking when I get BACK from riding. When I was checking it after a ten minute warm up before riding, things were iffy.
Mark
I'm making an assumption about the lack of clearance based on the vibration going away on hard pack. It has also gone completely now that I have reverted back to (what is now the center) bolt hole. The track was not touching in the tunnel, just closer than it would be in the upper bolt holes. Unfortunately I changed several things when I did this mod including loosening the track about three full turns of the adjusters, as well as changing to using only two inside rear idler wheels. Again though, I'm not feeling it anymore since I went to the center bolt hole in the rear bracket.
Rode for six hours today and only did about 20 miles in one steep clear cut, which should give a good indication as to how often I was digging out (I think I was burried 30% of the time). I could sink past my waist in new snow. We have been getting a bunch here in the NW (Mt. Hood) with the local ski area just breaking 400" so far this season, most of it very heavy. The machine felt more top heavy, and tended to trench more easily than in the mod setting, but it could have been the amount of new snow to some extent, every day is different. I'm going to see if I left enough room between the new hole, and the upper stock hole to drill an in between setting. That 3/4" really makes a big difference.
Maybe some of my other settings aren't quite right. What If I make the MPI transfer straps a little tighter so it doesn't open up as much? What about the front limiters? Searching provides plenty of conflicting info on that setting (I'm about in the middle).
Thanks for any info on your settings ('03 RX1 MT, stock skid)
On the plus side, it seems that I'm not using oil since I've been checking when I get BACK from riding. When I was checking it after a ten minute warm up before riding, things were iffy.
Mark
Thatspec
Extreme
Lincoln,
The transfer kit was installed when I drilled the holes. I measured the distance between the two stock holes, and went up the same distance (also kept holes in line, angling back slightly). Same on the center bracket.
I would suspect the suspension is partially compressed while the vibration is present. It happens only in deep snow from about 1/3 throttle on up. I love the handling in the mod position, just afraid I might be screwing something up. The sled seems to want to ride with the nose higher, (skid lower) in the stock position. Seemingly much more likely to trench if you let off the throttle at the wrong moment. In the mod position the sled rides flatter (again, could be these particular days snow conditions).
MT
The transfer kit was installed when I drilled the holes. I measured the distance between the two stock holes, and went up the same distance (also kept holes in line, angling back slightly). Same on the center bracket.
I would suspect the suspension is partially compressed while the vibration is present. It happens only in deep snow from about 1/3 throttle on up. I love the handling in the mod position, just afraid I might be screwing something up. The sled seems to want to ride with the nose higher, (skid lower) in the stock position. Seemingly much more likely to trench if you let off the throttle at the wrong moment. In the mod position the sled rides flatter (again, could be these particular days snow conditions).
MT
Thrusted Vector
Expert
I never used the MPI transfer kit with this set up as it make front of the skid drop too much and starts hitting the rail protectors.This set up was designed to work with a stock skid,the MPI kit was designed to work with the skid in the stock position,but my set up and the MPI kit won't work together.what happens is the rail tips drop out to lift the machine out of the snow,but they drop out too much and start rattling the clips,this can get dangerous ,the rail tips can fall off and spear the track,take a look at the rail tips,you'll probably see that are scuffed up.
Thatspec
Extreme
Thanks Lincoln,
You may have saved me a speared track, pretty scary. I couldn't get a very good look in the dark but could see the side of one of the tips is pretty scuffed. So snow build up likely has nothing to do with the vibration.
What if I tighten the front limiters further? That might serve to keep the tips away from the track, but will it increase my "trench angle". I like the handling of the mod position quite a bit better. Ultimately I will probably spring for an M7 skid but this has got to get me through the season.
MT
You may have saved me a speared track, pretty scary. I couldn't get a very good look in the dark but could see the side of one of the tips is pretty scuffed. So snow build up likely has nothing to do with the vibration.
What if I tighten the front limiters further? That might serve to keep the tips away from the track, but will it increase my "trench angle". I like the handling of the mod position quite a bit better. Ultimately I will probably spring for an M7 skid but this has got to get me through the season.
MT
Thrusted Vector
Expert
Actually the reason you trenching right now is because when the skid with MPI kit and the susp. mod transfers weight,the attack angle is severly increased and the track has now turn into a churning wall.To check this ,lift the back of the machine and put a milk crate under the back and push to load the suspension and you'll see that the attack angle will get real steep,I wouldn't be surprised if you're not ratcheting like crazy.So you could try and pull the limiter straps in,but then that limits your front skid travel. Linc
Thatspec
Extreme
"Ultimately I will probably spring for an M7 skid but this has got to get me through the season. "
Correction;
162 M7 skid being shipped this week from Troy at RV. I may not get it installed this season though...
Correction;
162 M7 skid being shipped this week from Troy at RV. I may not get it installed this season though...
Thrusted Vector
Expert
That'll lighten it up.
geezee1957
Newbie
I did the mod and it works great. stock otherwise. I did buy an MPI kit but now I dont think I need it
Thrusted Vector
Expert
Don't use the MPI kit if you're going to do that mod.Lincoln
If you've got the M7 skid coming just put it in. Don't waste half a season on the proaction when you could be on the M7. Here's a few pics of mine. I built a new Cromo front arm for mine and made it wider to fit the RX tunnel. The skid in the pic as it sits there is 45 lbs. The stock proaction I took out was 76 lbs with all the wheels and transfer rods etc. You will need to add some spacers to yours when you install it. In the sideview pic the skid doesn't have any limiter straps installed yet so thats why the approach angle looks steep.
Attachments
FastAction
Expert
thats going to be a good looking sled. Lets see it when all put back together