VJ_Mazalin
New member
my buddy and i are having some questions on this. I just put a set of slps on my viper mtn, i have the head gasket mod done, air box gutted, ysy with a shim in the primary, no rivits in the outter hole and a 13.3mm rivets in the inner hole for a gross weight of 44grams on each arm with 8nd10 arms. the Attck system from Holtzman.
the problem iam having right now is that when i hold it wide open in the garage its reving at 8600 at 1100ft. now when i go up to 5-9000ft is it going to drop the revs?
and do i have to rejet it up to sizes? even tho the holtzman is on there?
the problem iam having right now is that when i hold it wide open in the garage its reving at 8600 at 1100ft. now when i go up to 5-9000ft is it going to drop the revs?
and do i have to rejet it up to sizes? even tho the holtzman is on there?
mod-it
Member
SLP triples should be set to turn 8900rpm.
VJ_Mazalin
New member
so do i have to rejet this thing??
VJ_Mazalin
New member
anyone?
you gotta run it on snow to see what rpm,s are. Your gonna drop 5-600 rpm,s at higher elevation which means reclutching.The attak will do a good job of changing the jetting for you as long as your good for 1100' now.
VJ_Mazalin
New member
were planning on going on the 21st i just don't want to get up there and be totally under powered, if worst comes to worst i'll drill out the rivets i have in the inner's when iam up there just to get me by for the weekend.
mod-it
Member
I'll try to help, but not sure why your rpm's are down so low. Also, on the back of your slp can there is a bracket that comes out of it with a rubber end riveted into it. The rivet is in the center of the rubber and over time will rub through your pull rope/recoil housing. I put some hi-heat silicon (the same stuff you use to seal up the pipes going into the can) over the rivet and used a heat gun to get it to set up before re-installing it. It takes quite a while to rub through, but definitely address it. NOTE: I have no idea if this will affect you since you have reverse. Never looked under the hood of one with reverse.
- First, your clutching. Unless the different primary spring your running is affecting it that much, I can't see why your only getting 8600. My first thought is could you possibly have a power valve that is stuck or pulled through? That can make it drop rpm's. When my sled had no flo-rites in the dash, just the pipes on it, I was running the same weight in my primary as you are now. By the way the 8dn-10's are 39.75g & the 13.3mm rivets are 3.1g, so your total is more like 42.85g instead of the 44g you said. Anyway, SLP calls for the g-w-g primary spring (stock) at all altitudes. If you still have it, try putting it back on. Secondary should be a green spring set at 70* below 5000'. Above 5000' it should be wrapped at 80*. Helix should be a 47* below 5000', and a 43* above 5000'. I'm running exactly what they recommend, I run 5-7000': g-w-g primary with 8dn-10 & 13.3mm rivets in inner hole (after I put in flo-rites I had to add 10.3mm alum rivet to outer holes, rpm's jumped about 200). My secondary is a green spring wrapped at 80* and a 43*helix. I'm running the oem belt. With this set up my rpms were about 9000 on the trail, and when in the powder it pulled down to 8900...peak hp rpm. Perfect! Again, after I put in the flo-rites I had to add alum rivets to outer hole. I highly recommend flo-rites, they're actually the only way my sleds getting air right now...
Which brings up a nasty subject. Triple pipes on a Viper bring about a bog when powder gets on the hood screens. I believe that snow lands on the pipes and the steam that's created is sucked into the air box. Dipped pipes seem to help, but I recommend blocking all underhood air. Not the outside screened vents (it needs the cool air!), but the openings on the inside of the hood that allow underhood air to funnel through and into the air box. There is a big thread in the mtn section from last season if you want some reading on it. I read that blocking the underhood air didn't work for many, but it seems to have done the job for me. All I'll say about that is there are many little openings that are easy to miss, make sure they are ALL blocked. I simply used duct tape.
As far as your jetting, if Turk (Guru) says your compensator should be fine then I would go with that. I would still do a few plug checks at first, way easier than the alternative.
- First, your clutching. Unless the different primary spring your running is affecting it that much, I can't see why your only getting 8600. My first thought is could you possibly have a power valve that is stuck or pulled through? That can make it drop rpm's. When my sled had no flo-rites in the dash, just the pipes on it, I was running the same weight in my primary as you are now. By the way the 8dn-10's are 39.75g & the 13.3mm rivets are 3.1g, so your total is more like 42.85g instead of the 44g you said. Anyway, SLP calls for the g-w-g primary spring (stock) at all altitudes. If you still have it, try putting it back on. Secondary should be a green spring set at 70* below 5000'. Above 5000' it should be wrapped at 80*. Helix should be a 47* below 5000', and a 43* above 5000'. I'm running exactly what they recommend, I run 5-7000': g-w-g primary with 8dn-10 & 13.3mm rivets in inner hole (after I put in flo-rites I had to add 10.3mm alum rivet to outer holes, rpm's jumped about 200). My secondary is a green spring wrapped at 80* and a 43*helix. I'm running the oem belt. With this set up my rpms were about 9000 on the trail, and when in the powder it pulled down to 8900...peak hp rpm. Perfect! Again, after I put in the flo-rites I had to add alum rivets to outer hole. I highly recommend flo-rites, they're actually the only way my sleds getting air right now...
Which brings up a nasty subject. Triple pipes on a Viper bring about a bog when powder gets on the hood screens. I believe that snow lands on the pipes and the steam that's created is sucked into the air box. Dipped pipes seem to help, but I recommend blocking all underhood air. Not the outside screened vents (it needs the cool air!), but the openings on the inside of the hood that allow underhood air to funnel through and into the air box. There is a big thread in the mtn section from last season if you want some reading on it. I read that blocking the underhood air didn't work for many, but it seems to have done the job for me. All I'll say about that is there are many little openings that are easy to miss, make sure they are ALL blocked. I simply used duct tape.
As far as your jetting, if Turk (Guru) says your compensator should be fine then I would go with that. I would still do a few plug checks at first, way easier than the alternative.
Essarex
New member
Guys, guys, you're way off track here, stop giving him directions to change things based on him reving the sled on a stand! Turk already made this point. There will be no torque feedback thru the helix on a stand and it will surely underrev until the primary is fully shifted out, and then and only then, will the revs climb past 8600. If they are not climbing past 8600 with full throttle on a stand, with the primary fully shifted out, then something else is very wrong. BTW, there is no practical purpose for reving the thing out on a stand.
tedgoesfast
New member
ive seen my sled rev 1500 rpm lower on a stand you have to have real conditions for rpm to be right and true the secondary has to be loaded from the track it slows shifting down and rpm comes up aslo motor has to be loaded to get jetting proper
mod-it
Member
Learn something new everyday, never rev mine on a stand so had no idea. I would have thought that it would over-rev with no load on the track. I mainly just posted SLP's clutching recommendations.
This is actually good news for him. By SLP's clutching chart, he should be real close with what he has in there. I would still put the g-w-g back in and a 43* helix. My sled improved from pulling a friends sled 1 length to about 3 lengths when I went to the 43* from the stock 45*.
I do still recommend some flo-rites and blocking the underhood air. Trust me, you'll be pretty cranky when your buds are ripping up the powder and your sled pukes every time you get off the trail and snow blasts up onto the hood.
This is actually good news for him. By SLP's clutching chart, he should be real close with what he has in there. I would still put the g-w-g back in and a 43* helix. My sled improved from pulling a friends sled 1 length to about 3 lengths when I went to the 43* from the stock 45*.
I do still recommend some flo-rites and blocking the underhood air. Trust me, you'll be pretty cranky when your buds are ripping up the powder and your sled pukes every time you get off the trail and snow blasts up onto the hood.
A K MtnViper
New member
You can trust slp's recommendations on jetting, needles and clutching to get you close enough to have a lot of fun.
VJ_Mazalin
New member
OK, thanks MOD IT for the reply and the info.
just a few more questions i have, can u adjust the helix that i have (stock one) or do i have to just pick up a new one??. yes i have the stock primary spring i just put one in from a stock RX1 just to bring up the revs some for a little extra kick off the line. i'll leave it just cuz it only is 4100 or 4200 now. thats not a big increase from 3900.
and i think why my revs were so low wide open was because i was using my second throttle and it wasn't pulling wide open all the way i noticed it before i went away to work for a week. when i go back i'll try it again i'd say it should be 9000 again cuz i never had someone there to hold the back of it up just for me to see it rev again.
so MOD IT, i have the primary right with the set-up i have now?? and i know my total weight is 44g i weight it on a scale, mybe i have differnt rvits in it then i thought.
so my main thing now is the helix, i'll have to take the secondary off to find out for sure what its wrapped at but iam 99% sure its at 80.
thanks for the great inFo guys!!
\VJ
just a few more questions i have, can u adjust the helix that i have (stock one) or do i have to just pick up a new one??. yes i have the stock primary spring i just put one in from a stock RX1 just to bring up the revs some for a little extra kick off the line. i'll leave it just cuz it only is 4100 or 4200 now. thats not a big increase from 3900.
and i think why my revs were so low wide open was because i was using my second throttle and it wasn't pulling wide open all the way i noticed it before i went away to work for a week. when i go back i'll try it again i'd say it should be 9000 again cuz i never had someone there to hold the back of it up just for me to see it rev again.
so MOD IT, i have the primary right with the set-up i have now?? and i know my total weight is 44g i weight it on a scale, mybe i have differnt rvits in it then i thought.
so my main thing now is the helix, i'll have to take the secondary off to find out for sure what its wrapped at but iam 99% sure its at 80.
thanks for the great inFo guys!!
\VJ
mod-it said:
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mod-it
Member
You should be close on your rpm's with what's in there. Remember what the other guys posted, you can't test it by running it in the shop with no load. But your right on with SLP's chart for weight.
The helix is up to you, stock is a 45 degree. SLP calls for a 47 below 5000' & a 43 above that. Since you live and ride below most of the time, it's up to you. I personally wouldn't want to buy a 43 for a one-time trip, and then need to buy a 47 (you said you normally ride at 1100') for back home. You'll be giving up a little performance running the 45 instead of the 43, but not a huge amount. I guess it depends on how competitive you are, lol.
The helix is up to you, stock is a 45 degree. SLP calls for a 47 below 5000' & a 43 above that. Since you live and ride below most of the time, it's up to you. I personally wouldn't want to buy a 43 for a one-time trip, and then need to buy a 47 (you said you normally ride at 1100') for back home. You'll be giving up a little performance running the 45 instead of the 43, but not a huge amount. I guess it depends on how competitive you are, lol.
VJ_Mazalin
New member
hahaa, well iam a little!! 
buti mainly use it for up top i hardly ever ride at 1100 feet don't get much snow around where i live.
But iam just worried about the jetting, my buddy believes that i should go up 2 sizes????
buti mainly use it for up top i hardly ever ride at 1100 feet don't get much snow around where i live. But iam just worried about the jetting, my buddy believes that i should go up 2 sizes????