Belt issues on the 850

[Rotax_Kid]

FYI on the Goodwin bolt set...Checked the bolts tonight. Looked like they will both fit the Goodwin weights without issue. Loading 2 largest weights on the 38mm pin gets me almost to 23g per arm.

My suggestion to anyone buying the Goodwin kit is to buy the 35mm kit if you have high alt clutching. This way you have both a 35mm and a 38mm pin as the 38mm is stock. Plus you save yourself 10 bucks. I feel this will be enough to operate the high alt clutching at my 1600ft and be low enough to cover the low alt clutching I also have.

 

[Rotax_Kid]

Most have likely not had a Pdrive apart yet. THe primary springs are very different. I originally thought this was a QRS spring the first time I took one apart. Here's a reference picture to show the difference in size between a Pdrive primary spring and a TRA primary spring

 

[Rotax_Kid]

For reference, here's what a 951 ramp looks like. I'll shoot a picture comparing it to the 967 when I get my primary tools back.

 

[unimog]

What are the stock gears on the G4? I have been running the C3 Belt drive on previous sleds so I've always geared it down when ordering them, they aren't available yet though.

 

[Rotax_Kid]

What are the stock gears on the G4? I have been running the C3 Belt drive on previous sleds so I've always geared it down when ordering them, they aren't available yet though.

19/45 112p chain for 154
21/51 116p chain for 165

 

[snopro]

Checked BRP community thread yesterday and still the feeling by dealers and BRP service in Sherbrooke that this is a PDI issue. Oil inside the clutches,outside of clutches and saturated foam in the drive belt area. They are also reminding everyone that belt deflection is critical. This engine hits a lot harder than the 800 did. If there is a problem they are playing it close to the vest. Our store is at 4 weeks with units out and still not hearing any complaints on belts. I phoned another area dealer buddy and same thing. We are just not seeing any issues yet?

 

[RGM]

They are also reminding everyone that belt deflection is critical.

Yup! Most guys run way to loose or never even check it. LOL some guys don't even know how to change a belt!

 

[Merc63]

I have about half a mm of clutch above the bottom of the belt Valley, is that fine to run like that for a day or two or adjust it out?

 

[snopro]

I have about half a mm of clutch above the bottom of the belt Valley, is that fine to run like that for a day or two or adjust it out?

A good starting point is running that "valley" on the belt even with the top of the secondary sheaves. Or with the track in the air have the track just starting to roll at idle but easy to stop by pinching it with two fingers they say.

 

[RGM]

I have about half a mm of clutch above the bottom of the belt Valley, is that fine to run like that for a day or two or adjust it out?

I never go by how high above the secondary the belt rides anymore. I always just push the belt between the primary and secondary and see how far in I can push it. About 1" is good. Basically you want it tight enough that the sled won't move at idle or have problems going into reverse.

 

[tex78]

My dealer told me with azz of sled in the air, and at idle, tighten till with track turning at idle, when to put brakes on if it drops rpm on cluster it's too tight, so tighten till brakes don't drop rpm

sent while drinking tea's

 

[brian h]

i agree with snopro and rgm, just checked one and belt was too loose,either way of doing belt tension works in my opinion. belt was too loose and after riding will need to be re-adjusted. i feel this is why possible some guys are having belt issues,a loose belt,with extra hp will generate heat

 

[SidewaysInto3rd]

Belt #2 blew today.

- belt lasted 50-60 km. No real riding, just cruising around first 2 days (had gf out on her sled on her 1st day .. so just dug her out all day)
- more or less settled snow, no big hills, no big pulls
- belt broken in properly
- clutches cold to the touch before and right after blowing.. barely rooped around for 1-2 minutes and it exploded on a modest sidehill climb
- Clutches and belt were clean
- pipe sensor is in
- felt and foam still in, but no real heat generated anyway
- not a lot of black marks (therefore not a lot of belt slippage)
- But... belt marks at the bottom of secondary shift out as seen in pic
- Clicker 1, max rpm 81xx

All signs point to secondary overshifting ..

 

[Old Boy]

 

[Chrisco]

This looks like to me that it is possibly just wrong calibration.... new sled... new clutchs....gearing looks great. Most guys are seeing super hot clutches when the belts are blowing...well its not from the gearing. So inefficient clutching will cause belt heat...
Also under hood temps play a huge part in this also, if it cant vent belts will blow. MTNTK is working on a blow hole for the 850 as we speak and will send me one asap if someone would like to try one I would offer it up, As I ride polaris and dont have an 850. It may help many at least ride till BRP finds out the real problem. That is most likely calibration.

 

[SidewaysInto3rd]

This looks like to me that it is possibly just wrong calibration.... new sled... new clutchs....gearing looks great. Most guys are seeing super hot clutches when the belts are blowing...well its not from the gearing. So inefficient clutching will cause belt heat...
Also under hood temps play a huge part in this also, if it cant vent belts will blow. MTNTK is working on a blow hole for the 850 as we speak and will send me one asap if someone would like to try one I would offer it up, As I ride polaris and dont have an 850. It may help many at least ride till BRP finds out the real problem. That is most likely calibration.

When the first belt blew my clutches were so hot i almost burned my hand through my glove .. on the second belt they were cool as a cucumber

 

[dano30]

all these comments on the 850 belt burner, im scared to take mine out of the garage...

 

[Jake jenkins]

I'm pushing 300 km and no issues yet sled pulls strong


Sent from my iPhone using Tapatalk

 

[snopro]

all these comments on the 850 belt burner, im scared to take mine out of the garage...

Count how many have had problems out of the 120 posts and I'm sure you will feel much better?

 

[assaultn]

BRP Warrantied my first two belts and my dealer assured me they are looking into this and will have sorted out soon. Dealer also noted that my clutches and surrounding area had no oil residue as I cleaned everything very good before riding so I'm thinking we can rule that oil theory out in my case.