Thunder Products 911 Billet Primary Cover (Tested to 12,000rpm)

[NOS-PRO]

Now that Evolution Powersports has cracked the ECU for all of us Viper owners and able to raise the RPM limiter..... now is a good time to tell you about Thunder Products 911 primary clutch cover.

This cover looks great, straightens out the towers of the primary clutch, keeps the clutch from flexing at high rpm's and has been tested to 12,000 rpm. No need to purchase an expensive billet clutch. The 911 cover bolts right on and will not affect your clutch setup.

The large bushing will last many years and will not wear like the stock Yamaha cover bushing. Larger diameter = less wear on components.

Thunder Products has also incorporated a way to move the outer sheave closer to the belt so you don't have that "slam" when you hit the throttle. Simply dial in the adjuster to where you have about .015"-.020" of clearance between the belt and one sheave.....tighten the allen wrench and you are done

This is copied from Thunder Products website:
"
New 911 Response Clutch Cover by Thunder Products
The TPI 911 Response Clutch Cover turns your ordinary OEM clutch into a high performance, long life, premium clutch assembly.
Billet machined aircraft grade aluminum, the TPI 911 Response clutch cover adds rigidity to the clutch towers eliminating the normal flexing. The rigid clutch assembly along with the huge oversize cover bushing (250% larger) will keep the sheaves in perfect alignment. This will eliminate binding and produce fast, smooth and accurate up-shifting and back-shifting. Clutch and belt life is increased!"

Read the review from Sno-tech magazine 911 Response Clutch Cover

 

[birkebeiner]

Price?

 

[nherbst454]

Looks like 239.00 according to the article, but I didn't find it on their website yet.

 

[nherbst454]

https://thunderproducts.com/shop/911-response-clutch-cover/

 

[NOS-PRO]

$239.95

 

[STAIN]

I have the cover but not the adjuster....can I add it?

 

[NOS-PRO]

Your cover must be the earlier one. Hmmmmm, I would need to call Lonn on that one.

 

[NOS-PRO]

I have the cover but not the adjuster....can I add it?

After looking at some of the pictures of the old cover, I don't see why it would not work as the sleeves are used on both, shouldn't be a problem.

Can you get a diameter of the sleeve on your clutch cover bushing? I can compare it to mine and see.

Otherwise, give Lonn a call, tell him I told you to call him

 

[NOS-PRO]

I have the cover but not the adjuster....can I add it?

Stain, you are in luck! Talked to Lonn and yes....you can get that adjuster to work with your cover. Lonn does want you to call him as he sets up the covers in house so he wants to check the bearing and make sure there is no wear and that the bearing/bushing is straight.

 

[smoothride]

I talked to lonn today and ordered this cover and a new Gates belt for my 16 ltx and the clutch kit is coming with it. Will machining the clutch for overdrive help this setup to?

 

[STAIN]

Stain, you are in luck! Talked to Lonn and yes....you can get that adjuster to work with your cover. Lonn does want you to call him as he sets up the covers in house so he wants to check the bearing and make sure there is no wear and that the bearing/bushing is straight.

Thanks, I will do so once I get the sled in the garage.

 

[Studroes144]

I talked to lonn today and ordered this cover and a new Gates belt for my 16 ltx and the clutch kit is coming with it. Will machining the clutch for overdrive help this setup to?

Would be better to change gearing, if you have enough power to get some overdrive (stock sled doesn't have the power) you are running your clutches in a very inefficient setup. It's best to use a little taller gearing and keep the clutching running efficient for a trail sled.

 

[NOS-PRO]

I talked to lonn today and ordered this cover and a new Gates belt for my 16 ltx and the clutch kit is coming with it. Will machining the clutch for overdrive help this setup to?

Machining for overdrive would give you a little bit more on top.... not going to lie there. The kit is setup to get the best out of the sled without machining the clutches. Gearing would help a little also, but that gets real pricey with some of the gear combos I have seen. I was able to find a stock bottom reverse gear {40} and get a top gear {22}. I had to machine a spacer.

 

[smoothride]

Would be better to change gearing, if you have enough power to get some overdrive (stock sled doesn't have the power) you are running your clutches in a very inefficient setup. It's best to use a little taller gearing and keep the clutching running efficient for a trail sled.

Thanks I will leave it alone then.

 

[cannondale27]

Could just get the 141 gearing. It's cheap right from Yamaha.