02 SRX Clutching Suggestions

Thought I would bump this thread, I did some testing with the current setup just to see where I'm at now I want to fine tune. Engine is completely stock.

Current setup:

Primary: Completely stock for 2002 SRX

Gearing: 23/38 with 8T drivers --> 1.86:1 ratio

Secondary: Roller Rooster with 39/35 helix and green yamaha spring at 70*


WOT RPM is initially around 8800 then climbs to almost 9000 after a long run at about 170 km/h. I know this is not ideal.


I would like to leave my secondary alone if possible and tune/modify the primary setup. I think I would like to stick with the 8dn-20 weights as well since they seem to be a good match for all around riding.

I'm thinking of trying a WWW primary spring with 8dn-20 weights and loading them with 4.5 g in both holes. Will this be enough to lower my WOT RPMs to 8500 or so?
 

I had similar gearing to you with 8 tooth drivers and was always fighting an over rev. I went to 24/37 which is still lower than stock.
 
musselman said:
Thought I would bump this thread, I did some testing with the current setup just to see where I'm at now I want to fine tune. Engine is completely stock.

Current setup:

Primary: Completely stock for 2002 SRX

Gearing: 23/38 with 8T drivers --> 1.86:1 ratio

Secondary: Roller Rooster with 39/35 helix and green yamaha spring at 70*


WOT RPM is initially around 8800 then climbs to almost 9000 after a long run at about 170 km/h. I know this is not ideal.


I would like to leave my secondary alone if possible and tune/modify the primary setup. I think I would like to stick with the 8dn-20 weights as well since they seem to be a good match for all around riding.

I'm thinking of trying a WWW primary spring with 8dn-20 weights and loading them with 4.5 g in both holes. Will this be enough to lower my WOT RPMs to 8500 or so?
Click to expand...

gearing reduces load on the engine so its raises the rpm, along with a only a 35 degree finish angle on helix, again raises rpm.

stock the srx already has a 4.5 in the inner hole on the weight and a 3.6 outer so your only going to gain about 1 gram increase by switching to a 4.5 rivet in the tip(both holes 4.5 then) so thats only 3 grams more total, so your going to need to look into changing the primary spring to one of less shift force to reduce the rpms. A stock srx has a 45/128kg (y-w-y) so if you were to use the (w-w-w) which is 45/119kg it would drop the rpm down some along with your addition of 1 gram in the tip youd be close if you only need to drop 500rpm to be at 8500.

it may be well possible youll need to add a washer to the tip rivet to make it either 5.0 grams or 5.5 grams if your still over revving on a good long strecth, it may climb up on you yet so be prepared but you should be able to get it back down with that.
 
Just wanted to bump this thread again, I have made a few changes and have done more testing and would like some feedback.

I installed a WWW primary spring and added 4.5g rivet to the outer hole. I tried the 47/39 helix in the roller rooster with a silver spring at 70°.

This setup kept rpm at about 8400 on a long run but if I hit the throttle too quickly it would shift out too fast and bog. I'm thinking this helix is too steep or possibly the silver spring is too much?

I'm going to put in the 39/35 helix with a green spring at 70° and test again.
 
I'm a thinkin that silver is too stout. Now that I looked at the chart..... Green is the obvious choice. For some reason I was thinking red was right under silver. I fubared that one.
 
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I am pretty sure you are going to need a very stiff secondary spring in there to keep it from overshifting even with that helix. Easy enough to test and find out.

Sent from my SM-G920V using Tapatalk
 
Just another update, I swapped in the 39/35 helix with the green spring at 70°. I really like the feel of this helix over the other, much better response and backshift.

When cruising at 70 km/h on hardpack and hitting the throttle the sled will rev between 8600 and 8700 and pull hard up to 140 km/h then slightly back off. Then it feels like it shifts out and pulls again up to 160 ish when I ran out of room, rpm stayed the same.

So it looks like I need more tip weight still, what are my options when I already have a 4.5g rivet in there? Would I be able to use nuts and bolts instead? I have a gram scale on its way to weight everything.
 
you can add a washer under a new 4.5 rivet to get more weight, or you can run bolts and nuts in the weights. The only thing you need to be concerned with is to make sure the clearance between the inside of the spider pocket and whatever weight you add, it must have clearance and not touch the spider or bad,bad things will happen....lol

the washer is likely all you need to drop that small amount, usually a small washer will be .75-1 gram, just weigh it on a gram scale.
 
I have a Roller Rooster secondary as well and I would not run the green spring. I as well was doing some testing and swapped to a green spring, it did Not take me very long to switch back to the Silver and wrap it at 70 but for your application I would probably start with 80. My sled didnt bog down but was not nearly as snappy. with the green spring I could smell my belt slipping after a short burst mind you I have 9 tooth drivers and a Bender Red spring in the front with a 49-43 helix. When I hit the throttle sled revvs straight to 8100 shifts to 8500 and pretty much stays there. So again I would definitely recommend the Silver.
 
Thanks for the feedback guys. I will try the nut and bolt and shoot for 5.25 to 5.5g. Will definitely make sure to check clearance, I have been there before when bad things happen to the clutch, not good lol.

I think the green spring is working for me because my helix angles are smaller, seemed to work great and did not let the belt slip at all. I tried the silver at 80° with the other helix and it wouldn't shift out, just got stuck at 140 and wouldn't go anymore.
 
Well I ran it again on the weekend when it was warm and slushy, +3°C and was pulling 8400 to 8500 rpm.

Should I still add some weight to bring down rpm? When it was hitting 8600-8700 it was -30°C out and very hard snow.
 
If you dont mind wrenching, use the bolt technique and adjust clutching for conditions. If you want to set it and forget it, what temp do you encounter most often?
 
Yah would like to set and forget it, temps are usually around -10 average so will have to see what it runs in that temp.

Does it make sense to have lower rpms in the warm weather? I know it will be slightly down on power because of the warm air.
 
musselman said:
Yah would like to set and forget it, temps are usually around -10 average so will have to see what it runs in that temp.

Does it make sense to have lower rpms in the warm weather? I know it will be slightly down on power because of the warm air.
Click to expand...


 Yes if you change the jetting it will lose slightly less. But they love the cold, I have ridden in as cold as -10f and it was much snappier even at 0 was much better then 30.
 
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