WonÂ’t pull rpm

S

Seth437

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Aug 17, 2018
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New Hampshire
Hey guys, I have a 98 srx 700 that I bought used last year. Stock jetting, v force reeds, stock air box, a hauck helix with only the letter G on it for markings (so not sure what the angles are on that helix? If anyone knows that may help) Mbrp can. Comp test was good plugs look good ( light brown ). I serviced, cleaned and set the power valves ( they were pretty close anyway) belt is good and sits just above the sheeths on the secondary. I am only getting 7700/7800 rpm most of the time sometimes it will climb up to 7900/8000 on rare occasions but then it only stays there for a couple seconds then drops back down until IÂ’m going like 80+ mph then it will creep back up to 7900/8000. I have bumped the spring pressure up to 9 and 3 on the helix with no change. It was on 6 and 3 and I moved it up in 10 degree increments with no change in rpm. Please help

Thanks in advance. Seth
 

first off that helix is a 49-41. should have a green spring wrapped at 60-80 depending on your liking. I'm sure you already know that can is losing you power. If you already cleaned the powervalves i would start with the primary, (what spring, weights and how much weight do the weights have) and report back
 
blevis213 said:
first off that helix is a 49-41. should have a green spring wrapped at 60-80 depending on your liking. I'm sure you already know that can is losing you power. If you already cleaned the powervalves i would start with the primary, (what spring, weights and how much weight do the weights have) and report back
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So I was wrong about the marking on the helix. It’s actually an A I just went and looked. And it has a black spring wrapped at 120. It’s only wrapped that tight because I was trying to gain some rpm. It was at 90 when I got it.. and an orange primary. Not sure about the weights. Like I said I bought it this way. Is there a way to tell what weights are on there. If I take them off maybe? Will there be a stamping on them? And no, I did not know the can is losing me power. Would I be better off with the stock muffler?
 
Seth437 said:
So I was wrong about the marking on the helix. It’s actually an A I just went and looked. And it has a black spring wrapped at 120. It’s only wrapped that tight because I was trying to gain some rpm. It was at 90 when I got it.. and an orange primary. Not sure about the weights. Like I said I bought it this way. Is there a way to tell what weights are on there. If I take them off maybe? Will there be a stamping on them? And no, I did not know the can is losing me power. Would I be better off with the stock muffler?
Click to expand...

it will perform better with stock muffler
 
Replace the "black" spring with one the has a colored band painted on it. Think green:wink:. That way we know what preload you are running. There is no use doing much anything else until we know that.
Id personality just get a brand spankin new green one.
 
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hauck A 53-48 but measures 51-46. My guess to steep for ya need to know what weights are in your primary.
 
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Ok. Thanks I’m gonna pull the weights out and see what they are. Do I need to pull the primary to get the weights out?

Thanks to you both.
 
Ok, so the weights are 8BU 10 with an added weight in the middle and another one added at the tip. So not stock according to you guys. The spring in the primary is orange. Also noticed that the weights have a fairly significant wear mark/indentation at the point where it would first make contact with the roller at the initial engagement spot. Now what? lol
 
Those are Vmax-4 weights, alotta people run those for racing.
Yours must be loaded up a little too heavy on the rivets.
If it was mine, I would try and find some stock weights with a stock spring.
Will be tough to tune the clutches without knowing the spring rates of your orange spring.
If you do go back to stock in the primary, you MAY be able to use that hauck A helix.

Here is a set of 1999 Srx 700 Weights with rivets, may be the easiest and most cost effective way to go.
https://www.ebay.com/itm/98-99-01-Y...862644&hash=item33f22c8bac:g:uuMAAOSwri5bdrUD

Then it calls for a Yellow/White/Yellow Primary Spring PN 90501-603L2-00
https://www.ebay.com/itm/Yamaha-905...357032&hash=item3f94d10f86:g:CwkAAOSwnApZ5Mgg

With the secondary, they call for a red spring for the 1999 spec, with a 60* twist.
If your secondary spring does not have a small paint mark, I would replace it as well.
 
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Seth437 said:
Also noticed that the weights have a fairly significant wear mark/indentation at the point where it would first make contact with the roller at the initial engagement spot. Now what? lol
Click to expand...
They are junk.
Now w/ that said, you might just want to remove any weights/rivets that are in the tips. Just to see if you like the profile of that weight.
 
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With the secondary, they call for a red spring for the 1999 spec, with a 60* twist.
If your secondary spring does not have a small paint mark, I would replace it as well.[/QUOTE]

So just to be clear mine is a 98. So is what you said still correct with the springs and the weights you mentioned?
 
Could someone give a quick explanation of what the weights are accomplishing. For example. Does heavier weight make for faster shifting and/or effect peak rpm? And adding rivets/weights to the weight does what?
Sorry I’m a rookie when it comes to how to tune a primary clutch.
You guys have been awesome with your info so far and it’s much appreciated.
 
Heavier rivets in the weights equal less rpm, but more force on belt in a nut shell.

The weights I sent a link to are from a 1999 SRX, same sled as yours, will work perfectly.
So, as long as you are doing the clutching for a 1999, may as well do it all the way through is what I am saying.If you are going to replace both springs, may as well do it to match the weights you will be buying. (If you choose to go that route).

If you are new to clutching, I would not recommend keeping the 8BU weights, as you will have a very hard time getting them set up correctly.
Buying the parts I showed you will be the easiest way to get it to work perfectly.
 
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