well, I think I may have found the issue, or a number of issues I won't know until this weekend, but a hose some how got detached from what looks like some sort of "actuator" that is attached to the carbs. It's really hard to see, but there is a horizontal nipple that is between the carbs and the motor up around the frame support that is then attached to some electronic receiving device, that hose was off... I also went ahead and changed the Plugs..which resulted in one of my plug wires breaking..need a new wire now.. replaced the belt as even though it was in "ok shape" it was showing signs of wear, once I took the belt off I noticed insides the pulleys it was glazed and there was "black" stuff so i took some brake cleaner and cleaned that all out and replaced the belt with a brand new one. I also decided to change my chain case oil. Tomorrow I'll pick up a new plug wire and see how she runs.
Can't wheelie anymore :( 07' Rev 800r
- Thread starter brahm
- Start date
Sounds like you found the problem brahm ... the dreaded RAVE hose issue. Make sure you secure that hose as well as the rest of them with nylon ties, since they have a tendency to come off. This was a known issue on the '07s. Never a bad thing to swap out your chaincase oil and check chain tension. Your sled should run way better at high rpm with that hose reconnected 
Just curious what year your sled is?
Just curious what year your sled is?
Sounds like you found the problem brahm ... the dreaded RAVE hose issue. Make sure you secure that hose as well as the rest of them with nylon ties, since they have a tendency to come off. This was a known issue on the '07s. Never a bad thing to swap out your chaincase oil and check chain tension. Your sled should run way better at high rpm with that hose reconnected
Just curious what year your sled is?
It's a 2007 800r Summit Adr 151. Can you tell me more about the "rave" hose I tried to look all over to see what it did last nite but couldn't even locate it on the blow out diagrams of the motor/carbs.
Here's a link to a real good diagram resource. Just find your year/model and you'll have diagram and listing of all parts(look under 3D RAVE). Your RAVE valve is actuated by engine vacuum so if the hoses are loose or disconnected, your valves do not operate/open correctly and you lose peak rpm ... I had a hose melt and my sled would only rev to 7600rpm
http://www.partforyamaha.com/pages/parts/viewbybrand/6/Ski-Doo.aspxHere's a link to a real good diagram resource. Just find your year/model and you'll have diagram and listing of all parts(look under 3D RAVE). Your RAVE valve is actuated by engine vacuum so if the hoses are loose or disconnected, your valves do not operate/open correctly and you lose peak rpm ... I had a hose melt and my sled would only rev to 7600rpm
Ah nice, ya I was looking @ cyclepartsnation they have the same system. So basically at higher rpm greater vacuum draw, the larger it will open the exhaust valves.. no vacuum due to disconnected hose, means my valves choke off which in turns means I'll run to rich on oil/fuel thus foul out my plugs, which can eventually back fire if to much residue builds up. ..hmm seems like thats exactly my problem... can't wait to take her out tomorrow and find out how much better she performs.
Glad you found the problem brahm ... give a report when you get back. You're might want to clean your Raves soon as well ... mine were hammered with carbon deposits from that melted hose. Clean and inspect guillotines ... apparently there have been quite a few failures where the cast blades are breaking
If you want the skies to lift alot then let out some limiter strap.
Well it's not so much I want to lift the skies, more I want my sled to perform as it should.. and last season it yanked em. If I let out my limiter strap I may yank em now, but It won't help me figure out if something is wrong with my motor/trans that isn't transferring the power like it was.
ok.. update not really progress..but I've isolated a few things. I'm still stumped though.
I changed the plugs, belt, chain case oil, fixed the visible popped off the RAVE hose (couldn't find any others).. Sled runs GREAT at partial throttle, today though I really started paying attention to what is going on and I have a very good idea.. Just no idea why.
Basically under load and 3/4-full throttle (climbing, pow turns, ect) they sled will flash up to 7000+ rpm, then very quickly flash back down to about 6500 rpm if I don't feather it from that point, or let off and reapply the gas (which is a recipe for getting stuck lol) it will choke out and die. I tested this out today, while doing some pow turns, and some pulls up a decent sized hill. I tried to pin it from the bottom I'd get great MPH then about 3/4's up the hill the sled would fall on it's face and die if i didn't feather. I pulled the new plugs after such a pull ..and white. This stumps me, as If it was running lean shouldn't it be lean backfiring? (which it isn't)
Now here is the Kicker.. NOT under the load (ie trail riding flat, or down hill) I can pin the sucker it will yank the ski's pull to 7600+ RPM and it will stay there until I run out of trail.. it screams.
I'm at a loss.. Somebody suggested the clutch isn't "down shifting" i really don't quite understand 2stroke transmission setups like I do a th350, so any insight would be great.
I changed the plugs, belt, chain case oil, fixed the visible popped off the RAVE hose (couldn't find any others).. Sled runs GREAT at partial throttle, today though I really started paying attention to what is going on and I have a very good idea.. Just no idea why.
Basically under load and 3/4-full throttle (climbing, pow turns, ect) they sled will flash up to 7000+ rpm, then very quickly flash back down to about 6500 rpm if I don't feather it from that point, or let off and reapply the gas (which is a recipe for getting stuck lol) it will choke out and die. I tested this out today, while doing some pow turns, and some pulls up a decent sized hill. I tried to pin it from the bottom I'd get great MPH then about 3/4's up the hill the sled would fall on it's face and die if i didn't feather. I pulled the new plugs after such a pull ..and white. This stumps me, as If it was running lean shouldn't it be lean backfiring? (which it isn't)
Now here is the Kicker.. NOT under the load (ie trail riding flat, or down hill) I can pin the sucker it will yank the ski's pull to 7600+ RPM and it will stay there until I run out of trail.. it screams.
I'm at a loss.. Somebody suggested the clutch isn't "down shifting" i really don't quite understand 2stroke transmission setups like I do a th350, so any insight would be great.
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L
LRD
Well-known member
Spark Plugs:
I have a Land & Sea Dyno, back in the early 90's I learned the hard way that the only way I'd dyno any customers sled was with a new set of plugs. On a twin just taking out plugs that looked decent (not black and fouled) was generally worth 2 to 5HP. Generally when dynoing you can very plainly here them miss at full throttle and full water load, have to shut it down and change plugs. Note these same sleds sound fine when trail riding because of all the other noise!!!!!!!!!!!!!!!!!!!! Think of all the money guys
waste to gain 5 HP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
The worst case before I figured this out that every sled needed new plugs was a V-Max 4 that could barely get out of its own way. Because of its 4 cylinders and firing order, two pipes, couldn't here it miss, after WASTING a couple hours trying figure what was wrong with it I put in all new plugs and picked up the missing 25 HP!!!! Never ever dynoed another sled after this without new plugs!!
Personally on my sleds I go through a lot of plugs!!!!!!
This is a performance secret!!!!!!!!!!!!!!!!!!
When you add this to proper clutch rebuilding and springs etc., bearings in the chassis etc you can beat your buddys at will, thats what its about, right!!!!
Good Luck
I have a Land & Sea Dyno, back in the early 90's I learned the hard way that the only way I'd dyno any customers sled was with a new set of plugs. On a twin just taking out plugs that looked decent (not black and fouled) was generally worth 2 to 5HP. Generally when dynoing you can very plainly here them miss at full throttle and full water load, have to shut it down and change plugs. Note these same sleds sound fine when trail riding because of all the other noise!!!!!!!!!!!!!!!!!!!! Think of all the money guys
waste to gain 5 HP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
The worst case before I figured this out that every sled needed new plugs was a V-Max 4 that could barely get out of its own way. Because of its 4 cylinders and firing order, two pipes, couldn't here it miss, after WASTING a couple hours trying figure what was wrong with it I put in all new plugs and picked up the missing 25 HP!!!! Never ever dynoed another sled after this without new plugs!!
Personally on my sleds I go through a lot of plugs!!!!!!
This is a performance secret!!!!!!!!!!!!!!!!!!
When you add this to proper clutch rebuilding and springs etc., bearings in the chassis etc you can beat your buddys at will, thats what its about, right!!!!
Good Luck
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First of thank you both for your responses. I cleaned the outside of my clutch when I replaced the belt (removed all the black gunk ect), scrubbed it down with brake cleaner ect. As far as the spring, I'll take a look @ that well first I need to find it.. i'm not very familiar with 2stroke clutching systems hopefully it's easy to replace and doesn't need to be "pressed".
As far as plugs I just put in new plugs last sunday, my old ones were black and crusted. These new plugs have maybe 60 miles on them as of the end of day today (20 before we started)
Is the other stuff I should look clutch wise? What about fuel system? Could I be going lean under load due to a fuel (or lack there of) related issue not necessarily having to do with clutching?
As far as plugs I just put in new plugs last sunday, my old ones were black and crusted. These new plugs have maybe 60 miles on them as of the end of day today (20 before we started)
Is the other stuff I should look clutch wise? What about fuel system? Could I be going lean under load due to a fuel (or lack there of) related issue not necessarily having to do with clutching?
so to be clear, we are talking about spring #59 correct?
http://webservices.motorsportdealers.com/parts/partImages/BRP_SKI/4/IMAGES/04/M0727/19M0727B.Gif
http://webservices.motorsportdealers.com/parts/partImages/BRP_SKI/4/IMAGES/04/M0727/19M0727B.Gif
Before you go out and buy clutch parts, you need to clean your clutches thoroughly, inside and out. You'll find your primary is probably pretty gunked up inside when you pull it apart. You'll need a clutch press and button holders to simplify the disassembly and cleaning. I only use warm water and soap, then a good air dry before reassembly. Make sure your roller arms and rollers move freely in the primary and your rollers in the secondary move freely as well.
Some progress, still trying to diagnose the cause of the decline but, I'm seeing improvements today, we changed the clickers on the primary from 1 as it's been always set (prior to having any issues) to 4. Now I can pull a hill, sled goes to 8200 RPM and stays there...no powder but pulled a couple hills (lower alt then yesterday) So I'm wondering what would cause the sled not to function anymore with the clickers set at 1, but work correctly with them set at 4. Could it be the spring is weak, (or stuff is dirty) causing the clutch not to function properly with the lower angled cam, but under the higher pressure of a steeper angle it functions correctly (for now)
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any of you know any good online tutorials, or information where I can learn more about how to pull apart my clutches, and put it back together ect..
here there are 3 parts to this video It came in handy for me last week and made huge improvements to my sled. Buying the parts however are spendy I think I spent 220 at my doo shop for o-rings,sliders,cotter pins,and rollers,and a spring.
http://www.youtube.com/watch?v=92C7CZuHe2I
http://www.youtube.com/watch?v=92C7CZuHe2I
You said you have an 07 800R. I have the same sled, and it needs too be running at 8300 rps. If it is only hitting about 7000-7800, this is going to be a problem. Now you adjust the clickers up and got it to 8200 and it seems good. You need to have it hit 8300 on a climb. This may require 8500 on the trail to get 8300 in pow on a climb. Now if this was working before on the #1 setting, and now needs to be on the #4 or #5 setting, (and you have not changed elev.), you need to go through your clutch's and clean or repair the problem.
Sounds like you are on it.
Good luck.
Sounds like you are on it.
Good luck.
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Thank you for the response, it could be between 8200-8300 to be honest when I did the last hill pulls the skis pretty much stayed off the ground the whole way outside of some light skimming, I had one eye on the tach the other watching for trees, and some white knuckles haha.. Once I get in some good powder where I'll move slower but still pull higher rpms I'll be able to get a more accurate read. I do agree, I very much would like to pull my clutch, and give it a good clean and inspection but I think at this point (and this late in the season) I'm going to see how it performs in the powder this weekend (it's dumping right now) and if it's up to snuff make clutch rebuild a summer project. If she starts to dog in the deep stuff I'll start pulling her apart on sunday.
