Slow on top end?

norwegian

norwegian

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Hi
I have a 2002 srx with some kind of a heelclicker set up with a red spring, a 43 degree angle helix and a red secondary spring at 70 degrees. It has also a 1.5 inch ripsaw track. I'm sure the acceleration is awesome, but it's hard to say because it spins off the line. I will have to buy transfer rods.

The speedometer shows 87 mph (140 km/h) after 1/8 of a mile, and it barely touches 100 mph at about 85% (7800-8200 rpm) throttle in good conditions (Haven't been able to pin it all the way because the dcs activates then). Does this seem to be right or can I have a bent crank? Or does the heelclicker and track rob that much top end? Seems kind of slow to me..
 
the 1.5" track will definately lose you some top end. Have you figured out why your dcs is coming on? Have you cleaned the carbs this year? Is the jetting stock? Verify why the dcs is coming on, then get it out for a wide open run and see what happens.
 
I think I have an idea why the dcs goes off. The sled is jetted for 20f (or -7c) for my riding altitude. Carbs cleaned and everything But it's "never" 20f here, its always colder, ok it was 20f once, but it still came on, I think there may be some kind of safety margin here. 10f or 0f or colder is more common around here... I'm going to jet it up to -20f and then run a tempaflow and then see what happens. Speaking of -20f, its -20 here right now. :)
 
yea jet it for -20 or even -40 or so and see what happens. srx's and vipers have a very broad fuel curve, a little rich doesn't lose too much power on them.
 
I have no idea what jets to use for -40, because the book only shows down to -20.. Have you had any experience with dcs?
 
just run stock '01 specs, 150 in the pto and 148.8 in the other two. That should eliminate the dcs going off IF your carbs are clean.
 
That's what I'm running, it's too lean at 0-800 feet above sea level for anything colder than 20f...
 
ok then go up one size on each and see what happens. But that doesn't make much sense. I'm at about 800 feet above sea level here in wisconsin and down at -10*F i'm still PLENTY rich. If you are running stock '01 jetting you should have a lot of room left. You have any other mods done or anything?
 
Nothing more than a heelclicker clutch set up.. If you are around 800 feet, you're proably in the lower square of the jetting grid. 150 and 148,8s will, at 800 feet be good for -20f, but at the lower half of the 800 feet only good for 20 f according to the book.
 
h/c clutching

You need a shallow helix finish angle to pull good topend with heel clickers, if you run say a 47/37,48/38,48/36,50/40 helix, you can run heel weight and then only tip weight, and the sled will not only have good low/mid range but pull very respectable topend. leave the middle hole empty and move the weight to the tip and run a shallow helix finish angle, a 43 is not shallow enuff to pull alot of topend. clutch it for 8100rpm then let it climb to 84-8500rpm, this will get you the best of both worlds
 
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Ok, sounds like that clutching would take a lot of time. But the helix part I can fix ;) Thanks for the reply!
 
norwegian said:
Ok, sounds like that clutching would take a lot of time. But the helix part I can fix ;) Thanks for the reply!
Click to expand...

any good setup takes some tuning time, unless you are very lucky. Even experience will only get you so far, you will almost never be spot on the first try. ;)!
 
you asked????, I provided the solution

you can lead a thirsty horse to water but you cant make em drink.......
 
Thanks mrviper700. The closest I could find around here was a 51/40, is that ok?
 
51/40

its better but you need to be in the 36-38 range in finish angle to pull good tip weight and great top end, you could use a 40, but you cant use as much weight then, the more weight, the better the belt clamp=more topend. I am trying to say use it if its all you can get or have, but you may be able to trade someone for a better yet angle.

the heel clicker weight already acts like a progressive angle helix, it upshifts very quickly, with your helix start of 51, its more like a 53-54 start because of the weights, I would try something a tad smaller in the 47-48-50 start if it were me. you may get a overshift and then be hard pressed to regain the smooth revving of the engine thru the topend curve unless you lighten up the weights, and basicly thats defeating your purpose.
 
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I think I will be ditching the heelclickers alltogether. But for the jetting again, I remembered that my dealer told me that on #1 and #3, one of the 0,4 mm shims are missing on the needles. He had to order them. Could this be setting off the dcs as well?
 
I also remembered that my srx has a drag race set up for 1/8th mile, just with another helix I think. I don't know about the gearing. Anyway, this sled should be way faster than it is now.. I will have to look into the powervalves on the next service..
 
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