When should I replace 800r Pistons

[datmony]

I was at the shop looking at some loading ramps for winter and the guy there was asking me what sled I had. I told him that I had an 07 summit X 800r and he asked me how many miles were on it. I noted that there were 1600 on it and he said that I should be replacing the pistons in it because recommendation on them was before 2k. What are everyone's thoughts on that. I am not adverse to doing so but I wanted to get some other opinions on when that is needed. Thanks in advance.

 

[datmony]

Additionally what pistons should I run in it if I do decide to replace them. Thanks in advance.

 

[BIG JOHN]

1600 is a little early...I recomend 3000 miles "roughly" for the pro active tuner to keep there sleds in top form...BJ

 

[datmony]

That is exactly what I thought. I have been out of snowmobiles for a decade or so but grew up on them. We would always redo ours about that same mileage you note just didn't know if there was something special about the 800r that might mean they needed to be done earlier. Any thoughts on what you would put in when it is time to replace them? Thanks for the help.

 

[Anylizer]

I know of several that broke before 2000 mi. Doo it now, before the season starts. A.

 

[slim]

800r

I have a 07 800r with a shaved head on it and it has 2,988 miles on it, Never had a problem with the motor.

 

[datmony]

The key piece still missing for me here then is some thoughts on the types of pistons to put in. Been doing a ton of reading here on the boards and some people are raving about the aftermarket dual ring kits and then others hate them and say to just run stock. I am fine with stock ones but if there is a warranted reason to put some aftermarket ones in then I am interested to know. My primary goal on this sled is something that is reliable and decent on fuel economy. They have plenty of power stock for my current tastes and I want to be able to get back in the middle of nowhere and feel comfortable. Thanks for all of the thoughts.

 

[sledhead_24_7]

It really depends on how hard you ride the sled.

I know several people that have had pistons loose compression and worse before 3000. But then other get 5000 before doing anything. Just how you ride.

Me personally I would replace them now before the season starts. That way less of a chance of going down in the middle of the season.

As far as what piston to put in the stock ones doe work well. But you might consider RKT for his drop in piston, head, ECM re-curve kit it is supposed to make 15 or so hp.and help keep you from heat soaking the motor as fast so you maintain more hp also.

 

[kelwar]

my clutch side piston went out at 1900 mi but i think that was because of a bad rav valve ......

 

[Hiterhard]

wiseco piston replacement is my vote.

 

[Insaneboltrounder/sjohns]

thats going to be a lonely vote

 

[Original OT]

Miles alone should not be the determining factor. If you check the compression you should be between 120# to 125# of pressure on the 800R motor. If your below that it's likely time for new set of pistons & rings.

OT

 

[crapchaser800]

I would say it depends on how hard the motor has been used. Granted, I'm running an '05 800 HO and not the R, but I have 3100 miles on her and not the least bit concerned. I'm a firm believer of a good break-in period for longevity. IMHO, most of the guys I've ridden with that blow motors early in life took them from the dealer, sat for 3 months, trailered to the mountains and pinned the throttle up the first hillside 2 miles from the trailer.

I have a buddy with an '07 XRS with 4,000 miles on it and its been nothing but gas, oil and ride. Blew first belt last year at 3,200 miles. Not all '07's are ticking timebombs.

BUT, if you decide to put in new pistons, I've found it is hard to beat factory Ski-doo pistons. I had 2 sleds (both with over 8,000 miles on them) that I put Wiseco's in (cheaper, should have known better) and had problems within 1500 miles, even after break-in (and these were trail sleds used in northern WI and MN).

 

[snowcross338]

Go with factory pistons, wisecos are a good pistons if you are racing and eplace pistons every other race. I had about 1700 when mine blew, and then have about 3500 on the new motor, probably needs pistons now

 

[NoSecondChances]

I would say it depends on how hard the motor has been used. Granted, I'm running an '05 800 HO and not the R, but I have 3100 miles on her and not the least bit concerned. I'm a firm believer of a good break-in period for longevity. IMHO, most of the guys I've ridden with that blow motors early in life took them from the dealer, sat for 3 months, trailered to the mountains and pinned the throttle up the first hillside 2 miles from the trailer.

Yeah, what he said^^^. Break in the motor right, always start and warm up the sled before gunning it off the trailer at full throttle and then taking off up the trail at WFO with a dead cold motor. Normally, I start it on the trailer and let it warm up, then shut it off and let it heat soak while I put my gear on. Same applies for lunch stops/rest breaks, warm up sled after stopping for lunch and before taking off WFO and climbing the hill directly in front of you, (that you've been staring at for the past 45 mins).

NSC

 

[Original OT]

IMHO..The 1st, 2nd & 3rd pull of the rope on a cold sub-zero morning is HELL on all cylinders walls, pistons/rings. Having the adility to keep your sled in a warm shelter in between rides sure helps.

OT

 

[diamonddave]

If it's an 07, I'd be more concerned with your RAVE valves breaking than your pistons. Doo has updated these and aftermarket are available also. BJ's 3,000 mile mark is right on the money imo for us smart riders. There's nothing wrong with stock pistons.

 

[datmony]

What are the thoughts on the RAVE valves? I have been reading a good deal about them on the forums here as well and it sounds like there were substantial issues with them but that Skidoo was not standing behind the replacement of them until something went horribly wrong. Is that a correct assessment? In that case I would assume that a preemptive replacement of these would be completely on my dime. I am not adverse to that but would like to know the best plan of attack to address. Are the Doo ones or aftermarket better? What are the cost comparisons between each option? Who makes the aftermarket ones you note? Is there a way to determine if the RAVE valave spector is looming or is it just that they are all junk from the factory? I would appreciate any and all feedback that you all can provide and thank you for the very welcomed advice thus far. Definitely a great resource of information.

 

[Original OT]

What are the thoughts on the RAVE valves? I have been reading a good deal about them on the forums here as well and it sounds like there were substantial issues with them but that Skidoo was not standing behind the replacement of them until something went horribly wrong. Is that a correct assessment? In that case I would assume that a preemptive replacement of these would be completely on my dime. I am not adverse to that but would like to know the best plan of attack to address. Are the Doo ones or aftermarket better? What are the cost comparisons between each option? Who makes the aftermarket ones you note? Is there a way to determine if the RAVE valave spector is looming or is it just that they are all junk from the factory? I would appreciate any and all feedback that you all can provide and thank you for the very welcomed advice thus far. Definitely a great resource of information.

Keep the rave valves clean and free from sticking and they will work great. Recommended cleaning every 500 miles.

OT

 

[diamonddave]

Keep the rave valves clean and free from sticking and they will work great. Recommended cleaning every 500 miles.

OT

As usual, OT doesn't know what's going on. The RAVE valves were updated by BRP mid 2008. The 07 and early 08's have had issues cracking. Friend of mine had this happen around 1,400 miles. I believe (may be wrong) that supreme tool (aftermarket source) makes them also and was told that the price was about the same.

Here's a thread on dootalk about it. Didn't dootalk ban OT??

http://www.dootalk.com/forums/index.php?showtopic=298851&st=0