Ran clutching today, input would be great

S

Spinner18

New member
Joined
Jan 16, 2006
Messages
315
Age
37
Location
Virginia, MN
Set-up
8dn-20 4.5 gram each hole
stock yellow white yellow primary spring
red seconday spring, wound to 100* holes 1 and 9, tried 80 and 90 wrap
52-46 micro belmont helix

Did a few pulls with this today, 38-39* out about a 1/4 mile on the lake

From a dead stop, it would rev 8500, back off to 8200, then climb to 8350 or so...

BUT when cruising at 40-60 mph, if i go WOT from there, its VERY boggy. After 2 seconds it would then rev out. It pulled very hard from a stop

Speeds, I ran it about 10 times, each time on GPS, 101-104. Speedo read 109-110.

tried the 53/41 helix for the heck of it also, didnt seen to accelerate hard, rpms were at 8500, but would only pull 103 on the speedo, which was 97 on gps. that helix is garbage.

Why is it boggy so bad in midrange? Do I need to change to stock weight in the middle hole? will a lighter weight there clear that up, and possibly raise top end rpm just a tad?

Sled has stock exhaust on it, stock jetting etc. I weight 235 also
 
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you are doin better then me my friend.Installed new reeds here and man does the sled ever jump now..very snappy and the first time ever the SRX started in 2 pulls.At 65 mph I nail it and the ski's are coming up a bit still.So out of the hole launch is awesome..no hesitation.Climbs like crazy..pull you arms off feeling to 100 mph and that is were it will stop.Early morning my rpm's were higher at wot..like 8400-8450.Coming home in afternoon at wot only hitting 8000 rpm's wide open throttle..still getting to 100 easily.The new belt has definitely dropped my rpm's.Have completely stock setup in the clutches.
8dn20's with 3.6 inner and 4.5 outer.Helix is stock with red spring at 80.I just can't seem to get my wot rpm's but sled performed great otherwise.Just great throttle response today at about -5 celcius day and sunny.If I pin her on bare ice she will hookup..raise's the ski's and flies.
I had great luck late last season on mild days with the 51/43 helix..so will try her again to gain wot rpm's.In the corners on the river I am taking her at 80 mph and she goes around like on rails..hate for my handlebars to break at that point..lollll.My compression numbers after I came home were as follows:


mag--126 psi
center--125 psi
pto--126 psi
starts goods..responsive as hell and wild 0 to 100...just got to break it to at least 110-115 Last year was at 118 on speedo almost bare ice on a plus 7 celcius day with the 51/43..go figure.Warm temps all next week near 0 evry day right into the weekend.Got to figure this out soon.You at least are getting highter top speeds, but I don't have any hesitation or bogging going down.We have to find a solution man.... :o| :o| lol
 
i am thinking the hesitation/bogging is from the 4.5 rivets in the inner hole. i am pleased with the 104 numbers on a 38* day... hoping less weight in the midrange will clear everything up... going on a ride tomorrow, and going to have to ride it boggy... just have to make sure if anyone wants to race, that its from a dead stop, not 50 mph pull up and go, otherwise im f'ed.

blue, have you cleaned your clutches lately?
your early morning rpm's were higher prob cuz it was colder out than afternoon...

i also found out it runs better with the pipes smokin hot. also, my clutches were warm. not hot, not nice cold. could hold my hands on them all day, i feel the belt temps are really good... now if i could only find a way to get some lighter weights for my weight on a sat night... ha
 
im also going to check my needle settings tonight, i do not know what they were at, or if the previous owner moved the clip when he had the aaen pipes on it... is stock middle clip?
 
with the new belt after high speed runs..my clutches are nice and cool to the touch.Belt rides up all the way till about a 1/4 to 5/16 "from top of sheaves in primary.Being warmer out the snow will bw a little more sugary then nice crisp cold days.That will slow you down also.Remember I got my best speed on almost bare ice last year..shifted out good and climbed fast to 118.I miss that.... :o| But overal this damn 700 motor performs..love that midrange pull when I pin it..you have to hang on to the bars..lol
 
oh yeah..this year I am running 120 mega bites..last year nothing.Also I weigh aboiut 8 to 10 lbs more then last year..but still.I weigh about 178 to 180 without gear.
 
You are lacking throttle response because your set up is for best acceleration & top end. If you want to be fast you sacrifice backshift. You can,t have it all in clutching. You give something up to gain somwhere else.
 
But Turk.don't know if you were speaking to me..but I am at totally stock clutching and new belt...is this what came out of the factory for response??Can't figure why I am not running 8500 wot anymore.Clutches were all rebuilt a will back so it is not binding or worn out parts.Track is slightly looser and rotates on stand easily.There should be nothing to stop me..but if I was at that magic number of 8400 to 8500 wot..should show up higher #,s on speed.I also have stock gearing..nothing has changed there.I am stumped a bit. :o| Maybe a few drinks will help me forget about it. ;)!
 
Turk, initially what I have is both stock springs, and a more agressive helix initially, but finishes slightly lower than the stock helix. Stock 8dn-20 weights... It doesn't matter even with a stock helix in it I borrowed from a buddy. Huge midrange bog... Like way too weigh weight in the center. I can gradually accelerate from a stop, and when I hit about 40 the motor lugs down bigtime, and I give gas and bogs until speeds get higher. Don't tell me this sled stock did this...
 
better check out your carbs,maybe something got plugged up in the jets or something or your float level is off. Now when you say bog.you think it might be a clutching issue..like binding.You back off the gas and pin again..does it clear then.?
 
If I back off the gas and mash it doing 50, it holds current rpm, climbs slow for 2-3 seconds, then takes off like a rocket. Ran fine with the aaen pipes and some ****ed up clutching in there. Now with brand new stock springs and my helix, with 4.5 in each hole it's very doggy midrange. Not my carbs. I bet when I can get some 3.8 for the inner holes it will be perfect
 
if not..then replace your clutch bushings and check other bushings in the weights and rollers to.Sounded something like I went thru a few years back.
 
it ran good the day before with the aaens and that clutching. i should add this. when i tried that pink secondary spring, which is WAY stiffer than stock, the midrange bog would go away... so leading me to thinking on a stock machine, you can't really go more than the 3.8g in the center hole while running the stock springs, unless your running a shallower angle helix.

if it was faster with more weight, you would think yamaha would have more than the 3.8 grams in the inner hole... correct?
 
I gather the reason why you put more in the 1st hole is to get your launch rpm's to stay around 8200.But doesn't matter..if the snow is loose and sugar like..your gonna spin to hell.Noticed that today,and I have 3.6g in 1st hole.I launched hard..with studs yet and rpm shot up to nearly 9000 and dropped quickly when hooked up.
 
I didn't put it in there, guy before me did but had different springs and helix. It's too much weight, makes it super lazy in mid. I actually had really good traction, was packed and 1000 screws in the lugs. It should spin to 8500 and stay there. The too much weight initially spins it there, but midrange is lugged down to 8200 and creeps to 8300. I bet when I go to 3.s my top end rpm is spot on, no midrange lazyness... It's hard todescribe, but easiest out is while going 50 and punch it, rpm climbs VERY slow, then it takes off like a rocket. No matter how tight I would the red spring it wouldn't go right away at 50. With super stiff pink, it would go. Belt riding way higher, acting like a super low gear ratio so it could pull the weight then... Get where I am coming from?
 
But it pulls okay from a dead stop to top. Just can't get acceleration once already moving like 50. That shouldn't cause Belt to drop quickly. Because even if I hold it at 50 and give it steady increasing throttle accelerating once it gets past the doggy zone the rpms climb quickly. I'll try stock weight in 1st hole and post back new results next weekend. When I run the 53/41 helix with same spring settings it doesn't have that doggy zone as bad, shallower helix, easier to pull the heavier weight midrange... And then If the stock weight doesn't cure it, will go to next stiffer secondary spring although once everything is stock besides the helix it should be fine. The 52/46 isn't that aggressive...
 
Why don't you think it's too much midprofile weight? The sled literally ran great no issues with the clutch the day before... What do I check in the clutches? Also with the primary, there is a metal circular piece that fell out when I took the spring off, I set in te clutch, set the spring on the top of it, then put the cover on. Is that just an egagement spacer? Also, what do I check in secondary for binding? I figured if it was binding it wouldn't pull rpm...
 
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