I have a 2002 Viper that's overrevving on any given day, hot/cold or heavy snow doesnt even make a difference. Sled is completely stock, 2000 km, belt fine, clutches are clean/aligned (still on original belt). The sled pulls 88-8900 rpm anytime w/ stock helix.
Tried a 51-45 helix last weak in hot weather, it made a difference in the low end - midrange at 8500 rpm, but past 40-50mph still pulled 8800+ thru top end. Wondering if I should try something with a steeper finishing angle or add more weight to the primary.
Seems something like 53-43 helix wont help this...
Tried a 51-45 helix last weak in hot weather, it made a difference in the low end - midrange at 8500 rpm, but past 40-50mph still pulled 8800+ thru top end. Wondering if I should try something with a steeper finishing angle or add more weight to the primary.
Seems something like 53-43 helix wont help this...
800
New member
Alot of them over rev, and they can use more helix at the start. Take that 51-45 you have (if thats all you have) put that back in and put more weight in the end of the weight (which probably won't be enough) or go to a softer rate spring at full shift, unless you want to go with a complete clutch kit.
jcc
New member
I would also put a new belt on it. If you are still on the original then that may be one reason for the over rev.
yamaholic22
Active member
put 4.5 gram rivets in the tips
n2oiroc
New member
a 48/40 advant edge helix fixed mine quite well. it works up to 8,600 on a long run over 80mph, otherwise its at 8,500.
I added the tip weights to mine and it ran perfect for the first 100kms and now its over reving again. I don't know what to do next? clutch kit ?
yamaholic22
Active member
n2 you should definately get those 4.5's in there, 8600 is still too high
800
New member
You know when I was out testing shock Vipers, Mine ran 8600 108.7 (119 speedo) so then I weighted it up for 84-8500 and it slowed down, 106. Put the other weights in went right back to 109. So the tach is off or thats where it wants to run. My "S" is the same way. Doesn't matter I just do what the Stalker tells me to.
Also, the Viper wieght will only accept 1 more gram of wieght from stock and that never seems to be enough to cure the 88 or 8900 that alot of them seem to want to run.
Also, the Viper wieght will only accept 1 more gram of wieght from stock and that never seems to be enough to cure the 88 or 8900 that alot of them seem to want to run.
cardguy
Member
For those of you with the over rev, If any of yous want to buy a set 40-10 Heel clickers, I have a complete kit for sale used 1 season,
KIT INCLUDES: red and gray primary springs, 3 40-10 weights, all adjusting hardware and instructions. $100
Also have a 48/34 helix. $40.00
KIT INCLUDES: red and gray primary springs, 3 40-10 weights, all adjusting hardware and instructions. $100
Also have a 48/34 helix. $40.00
yamaholic22
Active member
yea that could be that the tach is a little off. On the two vipers i clutched this year, they both gained a little top speed with the 4.5's in the tips, one had the stock 47 helix, one had a 52/44
DoktorC
Member
The Viper we run with revs 88-8900 and will consistantly run 114 on radar. I honestly don't thing the over rev hurts the Viper like it does the SRX. We know that the ignition box still has alot of timing in it up top (hence the pipe issues)..maybe they like to spin...
n2oiroc
New member
i have 8 tooth drivers with 2 teeth removed from the speedo gear. 8,900rpm 108mph. with the helix change and nothing else 8,500-8,600rpm 96mph.
yamaholic22
Active member
well if you changed it to a steeper angle helix, the setup probably doesn't have enough in the primary to pull the steeper angle of the helix at top end. Shallower angles will run more top end
I had my Viper running at 8400rpms at the start of the season and its night in day in terms of performance compared to over revving at 8,600rpms +. It pulls like like a mofo at 8,400rpms. I don't get why its over reving now again.
I spoke with a local tuner this weekend, the guy really knows his stuff but fiddles with skidoos mostly. He told me however that the reverse cam secondary in Yamahas had a tendency to not shift properly as soon as there was crud/belt residue on the sliding sheave bushing. That would make sense for a sled that starts to overrev after a certain time. I'll clean the clutch and see if there is an effect on rpm's.
Mine(02) over reved bad (9100) did hc 40-10's with 3.2g tip 4 g heel red spring, and a 48-40 Advant edge helix, now it is 8400-8500 no matter what conditions. Has 4000k on it now, and like yours started over rev at about 2000k.
yamaholic22
Active member
its a given that the clutches need to be nice and CLEAN, along with good parts and a new belt for this testing.