8BU may be good for a boosted application but suck for NA. I tried them on my Nytro with full mods and couldn't get them to pull over 8600...mind you I could have emptied the tip but still found the sled didn't have much snap with them.
I'm surprised I haven't heard of anyone running Drag n Flys....they worked great in the Nytro with Turks black spring set up
stingray719
TY 4 Stroke God
stingray719
TY 4 Stroke God
OK, the Viper clutch is very different than a Nytro. Put a clutch shim in a Nytro and all it does is raise engagement speed. Shim in a Viper wakes it up, if a Nytro kit would work I would not have lost half a season last year figuring this out.
OPO is a very stiff spring but very short. GWG is almost 89.8mm long and the OPO is only 82.6mm long. I could see how that would work in a Nytro with those smaller rollers but I have serious doubts in a Viper. But try if you wish and let us know you might find something we missed
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turbo800
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That's the whole thing, not alot of people are willing to share their clutch setup!
What I've seen posted so far...
Found another guy running almost the same setup as I posted earlier, except he was running:
43* helix and Cat Green secondary spring in 1-0
19/40 (2.105) gearing
Another guy running in his MCX 190:
Blue/White/Blue primary
MCX weights @ 77.8 g
Cat Purple secondary 0-1
39* helix
18/40 (2.22) gearing
162 Camo Extreme track
So how/why does the Viper clutching act differently than the Nytro?
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Good question..... I tried my clutch setup from my Nytro and it was like going from a street bike to a moped. Didn't like it at all. (ok, more like a 500 twin motorcycle to a 250 scooter) LMAO
Mountaintech
TY 4 Stroke God
Has the Viper clutch physically changed from previous versions?
stingray719
TY 4 Stroke God
Check the castings, they look different to me, and both my Vipers the clutch was much tighter than my other Yamahas were. Not sure though
larrypolaris
Expert
Good question..... I tried my clutch setup from my Nytro and it was like going from a street bike to a moped. Didn't like it at all. (ok, more like a 500 twin motorcycle to a 250 scooter) LMAO
Yeah. I put my Nytro kit in the Viper. Viper couldn't pull the same weight as the Nytro.
Power just wasn't there. Had to take weight out of the weights to make them work.
Studroes144
TY 4 Stroke God
How much weight? My setup compared to the same kit in a nytro only uses 1.3 less grams than the nytro
larrypolaris
Expert
I am running Hauck VP weights. It was in that range. Right around 2g. I need to check my log book for the exact amount.
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Good question..... I tried my clutch setup from my Nytro and it was like going from a street bike to a moped. Didn't like it at all. (ok, more like a 500 twin motorcycle to a 250 scooter) LMAO
Your FX Nytro was a 121" model with a 1.25" track. Your SR Viper is a 141" model with a 1.6" track. They will require two different clutch calibrations to make it work.
Studroes144
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Allen how does gearing compare from say a nytro xtx to the ltx viper?
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No, the stationary sheave is the same part number (it has changed 1 time, since it was introduced on the 2003 RX-1), the movable sheave is the same part number (that was introduced on the Apex, with a little more strenght built into it), the cover is the same part number (same part number that dates back all the way to the 1998 SRX), and the spider assembly is the same (introduced on the RS Vector when they were fighting the clutch noise on that model).
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It's within 1 mph, with the RTX/LTX Viper models actually geared slightly taller.
