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Discussion Starter · #1 ·
I need a bit of advice tuning in my sled, never had to mess with a not stock 700.

this is my setup
HTG twin pipes into a DG can.
Vforce reeds
No boost bottle for the moment, but I will be adding one.
Mag side has a 230 main, 48 pilot, 6.5 slide.
Pto side has a 200 main, 48 pilot, 6.5 slide. I dont know what clip the needle is in on either side.
There BOTH running lean.


And if you have ever clutched for these pipes any help would be appreciated.
 

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The only non-stock thing I see is the pipes. Don't know anything about HTG. Have you tried contacting http://www.htgracing.com/exhaust.php for advise?

What kind of carbs are on there?
How about elevation?
Only reason I ask is that your numbers sound wonky. I had PSI twins on my 98 for a while and was running 175ish mains with a 38 pilot.
With the stock pipe, I was running 165 with a 42 pilot.
My numbers are for Keihin carbs starting at 3000'.
 

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What elevation are you riding at???, without porting those pipes should not need mains over 210 unless your running it when the temperature is -20 or lower and it still depends on the elevation also, for under 3000ft the HTG's are good with 205's down to +10 or a bit lower, and why are you running such big pilots???, 48's are huge for the down low idle circuit, so I am baffled also as you say both cylinders are running lean with those big jets, my 770 big bore with porting and twins calls for 215's to 220's, so it sounds to me like you may have a air leak somewhere or something, the 6.5 slides are the leanest also, I run 6.0's in my 98 and 99, give us some more info and maybe we can help you get this sorted out, as for clutching you gonna want to engage between 42-4500, the last time I talked to someone at HTG about those twins (I have them on my 99) the guy I talked to said peak RPM was around 82-8300, helix and secondary spring choice will be up to how it feels to you, at a minimum a 48/36 or up to a 52/36 if it will pull it, if you can't get it to RPM with a 36 finish then drop the helix finish angle to something with a 34.
 

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Discussion Starter · #4 ·
I did not setup the carbs, it came this way when I bought my 97 rmk and swapped the engine into my 97 sks when the ignition coil fried on my sks. It has the 824 cylinders and newer style head. The last owner said nothing about having the engine ported so I am assuming it has not been.

I am running this sled at 0-3000 in elivation.
I had already swapped the carb boots when I did the engine swap so I know it is not getting air from there.

Yes the bottem end is a rich with the 48 pilots and I will be dropping them down a size or two. It does not foul plugs at idle (have let it sit for over 10min idling) but the plugs do come out black when I pull them.

I have a set of 5 and a set of 6 slides I can use insted of the 6.5's to fatten the mid range up if you think the 6.5's are to lean.

But it is running lean on the topend with the 200/230's.
The temperature was aprox 10-15F.

As far as clutching goes, I havnt pulled a weight to see what it has, I know it has a almond squar primary spring, which I will be replacing.

For the secondary, I have a few R8 helixs which are 50/34. I also have a SLP dial-a-spring Mountain Helix which I beleave is 46/32 and some stock 36 helixs. Im assuming the R8 is my best bet for now.
I know for the secondary springs I have some stockers laying around, and a SLP yellow/purple which is 40/95. I dont know if either of these will work with these pipes.

Dutchman
I am running the keihin carbs. Even with the stock pipe on my 98 xc engine (the engine that was originally in the sks, it has the 220 cylinders) I couldnt run anything less then 185/190's with 38 pilots and that was wit the 6.5 slides. And thats funny, I didnt relise vforce reeds and boost bottles came stock on these sleds...

There are ALOT of lakes and rivers around here, so I do hold my sleds opened up for pretty long periods of time. I like to have them run a bit rich on the topend so I dont cook the engine on one of the wide open runs. My friend used to own the 97 rmk I just bought, I think he sold it around 2005 to one of his friends which rode it only a few times a year. With this carb setup he would toast the topend everytime he would try breaking 100mph. He called it the nightmare. lol no kidding.

I hate only working 6 months out of the year, if I were working right now I'd jet everything fat and throw a tempaflow on this thing and call it good.
 

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crdude said:
And thats funny, I didnt relise vforce reeds and boost bottles came stock on these sleds...
Sorry, I said that wrong. What I meant was anything nonstock that would affect jetting.
 

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Discussion Starter · #6 ·
I figured that, I was just being a smart ass. lol
 

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Discussion Starter · #7 ·
I threw the 5 slides on and it runs way rich in the low-mid range. sounds like its almost running on one cylinder untell I open it up. I'm going to give the 6's a shot and see how they work.
 
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