Hey guys I could use some advise. I have a VERY low hour, like new 350L (1993). I am smart enough to know that the engine is solid.

My buddy has a 1997 400 scrambler. We've dragged race many, many times so I know a difference when it happens.

With that said, bone stock to bone stock, he would pull 1-2 lengths on me up to 40mph or so. Time and time again.

I got a AAEN clutch kit, installed an air cleaner (Moose). It had more pull out of the hole, but fell flat on top. I expected this as I am revving higher than stock and out of the stock pipe's power range. Now my buddy was pulling 6-7 lengths on me.

So then I got the AAEN torquer pipe and silencer. According to their website with the clutch kit and pipe I should be 5-6hp over stock. Used the 220 main jet that they supplied (vs 200 main stock).

With all that, I am now 3-4 lengths behind my buddy! I am slower than stock!! It just feels flat on top. It is more responsive, but mid to upper is just flat. According to their dyno sheets I should be reving out higher and making more power!!

What is the issue? Geez, for 400 bucks I should of at least been AS FAST as my buddy. Now I am slower than before. I might have to put the stock pipe on to gain some speed

Also, when I put the pipe on I put Boyesen reeds on. Again, according to their website this should be good for more top end and +1hp.

Is the 220 main too rich? I know 2-strokes run best when they are borderline too lean.

Argh!!

 

With all that you've done/invested in,better to talk to AAEN. If they're going to sell these products,they ought to have the facts to back them up and good knowledgeable people to help you.

 

I will call them monday. Its just funny though cause everytime I read about someone using a "stage one" kit (or pipe/clutch kit) they just raved about the HUGE difference in power and responsiveness. I am seeing nothing, and I went with a well known company such as AAEN. I'm glad that I have something to compare to (my buddy's 400) as even my butt-o-meter just felt that the new setup was flat.

Last time I had something like this happen was on a 250 trailblazer. I put a dynoport pipe on it and lost power as well. When I talked to dynoport they gave me every excuse known to man other than their pipe.. jetting, my engine was worn out, no clutch kit, just a bad model year, you name it.

I'll see what they say. I'm just curious if others have had something similar happen to them??

 

So what did they tell you?


Sounds like it is needing to many RPMs to upshift completely and just winding out. What all was in the clutch kit? I personally would figure out the specs on the primary spring and get one less aggressive. Even testing the stock one with the pipe would be interesting.

 

That is kind of what I am thinking. My biggest clue is that when I changed the clutch kit first using the stock pipe, I lost a TON of top end. The bottom end got much better. I am leaning towards something not being right with the clutching. It's AAEN's clutch kit, or what they recommend with the torque pipe.

AAEN has not returned my phone calls, yet.

It almost does seem like it is winding out too soon? From about 0-20mph me and my buddy are about equal. After that he pulls away quickly. Bone stock I was equal with him almost all the way.

Would it be the primary spring? I was thinking the secondary spring? I put the secondary on 2-2, and set it 1/3rd turn on the helix like the instructions said.

Other thoughts?

THanks!

 

did you change the weights as well? are they adjustable weights . what was the secondary set on stock? sounds like you have either too much primary spring or weights or the secondary is letting you top out too much. I know in the 4 stroke side of it when I playd w/ my 800 I would gain on one side and loose on the other until I figured the best primary spring for me. did you pull your plug out to see how it's burning w/ the bigger jet? sometimes people do not realize when you put a bigger pipe or an air filter that w/ out the correct all 4 set up(clutching, pipe air flow and jetting that most the time you'll loose more then you gain. imo.

 

For the driven clutch the service manual says 1-1 would be the next step softer. And then 2-3. Softer meaning it will allow an upshift sooner, downshift later. Basically bring the RPMs down. Might be worth a shot if you want to experiment. Also it mentions about 5 times not to leave out the spacer washers so make sure you don't have any of those left over on the bench lol


I would venture to guess they need to send you a weaker primary spring.

 

If weights are too light or the primary spring is too stiff max rpm will be to much and belt can't get into "high gear" at the top of the drive clutch. If the weights are too heavy,spring too light engine rpm will be too low and drive clutch will up shift too fast keeping the engine out of it's power band. You can remove up to 2 of the 3 shims from the rear clutch to take up for belt slack or wear,but one must always remain.This should be something Aaen should be able to help you with,that is if they ever respond back to you,as they designed the clutch kit in the first place and should have had a thorough testing as to different weights,springs,etc along with using their other after market items at the same time..

 

Well first things first, I put the secondary spring (blue) on 2 sheave 1 helix. Oops, it was supposed to be 2-2 or stock. This would make it a little softer?

I did talk to Olva Aaen. He said the clutch kit is designed for the top end pipe and feels I am over-revving or out of the torque pipe power. It does feel flat on top. Ideally he said heavier weight would help but said I would get similar results using the stock secondary spring in a pinch. He thinks I am not upshifting fast enough? Or too high rpms? Does this sound right?

Or do you think I should do the blue spring 2-2 and try it again. I'm thinking that's going to make the situation worse?

Again, from 0-20mph I am neck and neck with my bud. After that it's like he hits warp drive and is gone on me. Bone stock that wasn't happening! Top end is much worse now.

Thanks guys!

 

Try it. If its worse,you'll at least have an idea which way to go.