thunder shift kit

tripple_tripple01

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anyone out there running the thunder shift kit weights in their srx 700?if so how do the ywork for ya? just won a set on ebay, pretty cheap to ;)!, never hurts to have a lil clutching parts on hand
 

Run the majority of weight in the 1st hole & gradaully lessening to the tip. It might take 3-4 attempts but they work well when dialed in.You must tune em in for your riding style..racing; trail; mountain.
 
ok thanx. stock weights in the 01 srx 700 are 42.09 gram. and the base weight empty of these thunder shift weights are 39.6. i dont want to go over the 42.09 weight do i? or is it something im just going to have to play with, thanx again
 
For an SRX you're gonna have to load those weights up pretty good. I have almost 70 grams in my Heavy Hitters, and the base weight was only 48.2. Good luck with your setup!
 
If you keep the stock primary spring it will require less weight due to the more aggressive shift curve profile of the weight. I think the thundershift profile is very close to a 8dn-20 profile. Stack em side by side & see.
 
ok now im really lost. went to put the weights in and i have to install a set of tower bushings and change my weight pin, (at least thats what the directions say) i called thunder products and he said that i have to buy a different set of arms?????????????? the thing i dont get is why would it tell me to install that stuff if its not true??? anyone else run into this?
 
you can use the weights you have, you do have to install the bushings and keep out the stock set screws, the new bolts and the arms have smaller holes so you need to shim the yamaha clutch to make them work. I have all weight in end, small steel in the middle and nothing in the tip, works awesome, right to 8600 rpm off idle right to 185 km/h
 
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You need a set of conversion pins, You can use Yamaha bushings in those weights & they will fit. They presently come with Cat-Poo(comet) bushings which are thinner & need a spacer to fit.
 
i have a set of TP bushings that will allow the use of the small arctic cat pins with the TP ramps, they are smaller, they just press inside the inner clutch shieve where the stock pin went through making it smaller inside diameter....
 
I also have the thunder shift kit on my '01 SRX700. I was hoping to find where yours ended up, but I don't see any results posted here.

I keep adding weight to mine but I'm getting no where fast. I have 38.4 gram base weights and after upping the screw weights for the fourth time, I'm still seeing next to no change in shift RPM. I just put in the following: hole 1; 5.8 grams, hole 2; 4.2 grams, hole 3; 3.0 grams for a total of 51.4 grams per weight. Engaging at 4200 and shifting at 8800, but that's exactly where it was shifting before I just upped each weight 1.9 grams (1.2 added to hole 2 and .7 added to hole 3).

Those with experience in this area, how much more weight would you throw on to get the shift RPM down another 200 to 300 RPMs?
 
Maybe a slightly lighter spring? I don't know. That tripple-triple hasn't posted anything since March of 06 so hes probably not on here anymore. Maybe a spring with same preload but lower rate. What spring is in it now? I am not a clutch expert by any means. I'm just thinking of a theory. This would help me too if an experienced clutch guru would chime in to see if I learned anything with my 6 weeks of reading. You don't want to change the engagement, correct?
From my reading stand point, and little experience, I think you want the next rate lower with the same preload. That would keep the 4200 but throw the weights out a little faster to bring down the rpm. I am not even taking the secondary into consideration but wrapping the spring 1 less hole might do the trick also and cheaper if it works, then you don't have to buy a $30 spring. Again, I have a very limited clutching ability at this point.
 
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I backed off the secondary; it was at 80°; I put it back to 60° but I'm still shifting too high.

I don't mind if the engagement comes down a little so I'm going to reweight the primary again; going with the same 5.8 in hole 1, 5.0 in hole 2 and I'll jump hole 3 up to 4.2 grams (the most I've added to the tip at one time so far) and report back...but yeah, if anyone else has the low down on how much weight it typically takes at the tips to get the shift RPM down a few hundred I'd appreciate it.
 
It may or may not have made a difference. It seems like it's pulling harder but only short runs in th woods and I think I saw 8800 on the tach a time or two. Problem is, it's 50° outside and pretty much just slush. I may not get back to this until next year.
 


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