gabbett1
Member
So I have a 700 SX with triple pipes and some really different clutching. Used to be a fully built 800 by RPI Racing. They put on it and it still has a Comet 108 (if I remember correctly) primary and a Bearcat Arctic Cat secondary. The engine is back to stock other than the pipes. Took me a lot of playing around but I finally have the clutching right in the sense that I pull RPM and hold. Now I'm just not seeing speed. I'm getting maybe 90mph out of it. I marked my clutches and I have about 1/2" to 3/4" on the primary that isn't being worn. Is that normal? I am also running a gear that is one tooth down from stock. Did I go the wrong way? Perhaps I should go up a tooth from stock?
Any advice would be helpful.
Also, a side note, I have noticed my speedo is off by about 10 mph (90mph reads 80 on speedo). Any thoughts on how to fix that?
Any advice would be helpful.
Also, a side note, I have noticed my speedo is off by about 10 mph (90mph reads 80 on speedo). Any thoughts on how to fix that?
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if your running pipes you need to rejet! also ,are you geared to stock? if your running pipes you need to regear to get the most out of her ! need to know what kind of pipes so you can tuner up! the way it should be according to the pipes and how they make power! also clutching is going to be an issue.
gabbett1
Member
Yes I've already rejet the sled. I guess I should have specified that since I wrote it's stock but pipes. I also have the thin cylinder head gasket mod. I have EGT's on it to monitor it. I'm running AAEN pipes. It runs well. Just not going fast. Stock is 23/40. I'm running 22/40 right now.if your running pipes you need to rejet! also ,are you geared to stock? if your running pipes you need to regear to get the most out of her ! need to know what kind of pipes so you can tuner up! the way it should be according to the pipes and how they make power! also clutching is going to be an issue.
I thought about going to 23/38 like the SRX. Would I need to re-clutch again if I changed my gearing that much?
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sideshowBob
VIP Member
I believe the Aaen pipes need to run around 9000 RPM...22/40 is a good ratio and should give you over 100mph on a sx700 with pipes on the hard pack.
sideshowBob
VIP Member
If your speedo is out by that much there is something a miss...usually the speedos over indicate not under indicate.
How many teeth on on your track drivers?
What track are you running?
What is the track pitch? 2.52? 1.86? 3.0?
Lots involved when setting these sleds up
How many teeth on on your track drivers?
What track are you running?
What is the track pitch? 2.52? 1.86? 3.0?
Lots involved when setting these sleds up
gabbett1
Member
I've been told by a buddy of mine that races sleds that 22/40 is going to slow me down. I want good accel for sure, but I want top speed too. I ran the sled about half a mile and only got to ~90.I believe the Aaen pipes need to run around 9000 RPM...22/40 is a good ratio and should give you over 100mph on a sx700 with pipes on the hard pack.
gabbett1
Member
Track driver is stock (9 teeth I think). Pretty sure the track pitch is 2.52 but unfortunately I don't remember the exact track I'm running. Ripsaw 2 I believe.If your speedo is out by that much there is something a miss...usually the speedos over indicate not under indicate.
How many teeth on on your track drivers?
What track are you running?
What is the track pitch? 2.52? 1.86? 3.0?
Lots involved when setting these sleds up
gabbett1
Member
Was just out doing some tests. I got a GPS to test my MPH and it's actually dead on accurate... That means instead of doing 90 I'm only doing 80! Noticed something though. My tach on my sled looked to be right around 9000 but my EGT tach said 9350 one run and then 8700 on another. Not sure which would be more accurate and or if some variation like that is normal.
MURDER YAMAHA
VIP Life Member
Stock yamaha tachs I have found to be very accurate.
gabbett1
Member
I'm sure it is, but analog is much harder to see the fine numbers vs digital. That's why I'm wondering how accurate a Digitron EGT tach would be.Stock yamaha tachs I have found to be very accurate.
gabbett1
Member
Was out looking at the track. I think it might be a Camso Hacksaw.If your speedo is out by that much there is something a miss...usually the speedos over indicate not under indicate.
How many teeth on on your track drivers?
What track are you running?
What is the track pitch? 2.52? 1.86? 3.0?
Lots involved when setting these sleds up
what about your air intake box ? has it been modified? 700 sx's are very finicky with a modified air box!
gabbett1
Member
The air box is basically stock. I did remove the inner divider but that seemed to make little to no difference. A buddy of mine had a stock SRX he did that to and said it helped him so I tried it.what about your air intake box ? has it been modified? 700 sx's are very finicky with a modified air box!
74Nitro
VIP Member
If I remember correctly, I used to radar 110mph(on perfect conditions) with my 98 700sx.
Stock gearing.
Stock gearing.
MURDER YAMAHA
VIP Life Member
Tell us what weights, rivets and springs you are using.
I assume you are now using factory clutches?
I assume you are now using factory clutches?
MURDER YAMAHA
VIP Life Member
What brand are your pipes?
Stock clutching wont cut it with triple pipes, but if you know the brand, I can help you get to the correct RPM for that set of pipes.
Stock clutching wont cut it with triple pipes, but if you know the brand, I can help you get to the correct RPM for that set of pipes.
gabbett1
Member
No, I'm not using factory clutches. Like I said in the OP, I have a comet primary and an Arctic Cat Bearcat secondary. The primary has a light blue spring and 10MB weights (might need to go up just a tad in weight) and the secondary has a yellow spring. I have no idea what the spring rates are on either. I had help picking those out.Tell us what weights, rivets and springs you are using.
I assume you are now using factory clutches?
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gabbett1
Member
I am using AAEN pipes. I'm setting for 8900 RPM. My clutching is pretty much right there.What brand are your pipes?
Stock clutching wont cut it with triple pipes, but if you know the brand, I can help you get to the correct RPM for that set of pipes.
MURDER YAMAHA
VIP Life Member
Oh, ok, you said it “had” a comet clutch, figured that meant past tense.
I’m out as far as help with that goes, know nothing about those.
Would be very easy to clutch with stock clutches too.
Maybe someone else can chime in,
I’m out as far as help with that goes, know nothing about those.
Would be very easy to clutch with stock clutches too.
Maybe someone else can chime in,
gabbett1
Member
Ah, didn't mean to imply that it no longer had them. Fixed the OP to remove that confusion. I figured people would be able to answer general questions about how much of the clutches should be used by the belt to get full use. I received advice from one of the guys that used to be at RPI as far as springs go. Weights I figured out by trial and error. Just curious if for some reason I'm not getting full range of use.Oh, ok, you said it “had” a comet clutch, figured that meant past tense.
I’m out as far as help with that goes, know nothing about those.
Would be very easy to clutch with stock clutches too.
Maybe someone else can chime in,