02 Viper 85 MPH Top End?? 8500RPM! Is this normal top speed for this sled??

I did mine on the sled as well. Use the center primary bolt, or a longer one with the same threads to help pull it in, find or make a large washer to push against the cover. A piece of old slider may work. It also helps to get some longer screws to get the primary cover started then swap the standard ones in one at a time. Yes it is waaaay longer than the Yamaha springs and a pain but it can be done like this on the sled.
 
I have 21/38 gears in mine and have seen 118 on the dreamometer in very good conditions so I would think dropping down to stock 22/38 would still be plenty hi enough for your needs.
 
Born Yammie. Yup thanks for the Idea. I have a chunk of threaded rod in my garage. I found another way to do it too. take spring out and compress with threaded rod then ty wrap it to about 3 inches then put it back on bolt it down and cut the ty wraps! I think it should work?
I have a 22Tooth gear I am going to put in and report back.
J
 
That will probably work as long as you don't trap ty wraps down in the bottom. I'm sure your smart enough to figure that one out on your own :)
 
ya I will probly keep the wraps on the inside. Do you have any idea what the free length of the HC red spring is?
 
Ok Mr viper, 004.jpg003.jpg I took sled out for test run after installing weight. Heres what I found out:

Stock 22/38 gearing. Confirmed

HC Red Primary spring within spec
5.0 heel, 3.3 mid, 4.3 Tip weights

New Yamaha red dot sec spring
Dalton 48/36 cam
80 Deg twist

Machine engages at about 4700 rpm then jumps up to 8300 fast, then creeps up to 8400-8450 Rpm. Hard to compare top speed cuz it is about 34 here today and the trail was sloppy, but I think it would be about the same. Def NOT 110-120 on speedo! I took pics of the marks in the sheeves. Def not shifting out all the way. Black marks on primary are about .900 from top and secondary about .900 from bottom. What do ya think? Im surprised top rpm is about the same since i put alot more weight on it.
J
 
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I think that red dotted secondary spring is just too little. For the 2 strokes at least, Yamaha has/had four options: brown (for like BR 250), red, green and silver. When I'm running a HC set up, I don't even consider the red, I go with the green or a Hauck red (which is longer and stiffer). I have a HC set up with a hauck red spring in secondary and a pretty steep helix for trail riding on my MM 700 (01), and I get 82 mph on the speedo and it goes there fast enough to beat pretty much every modern stock 600 out there. In really good conditions, I had 90 on that sled on speedo. It has still got the single pipe.
 
norwegian, yup your MM700 setup sounds exactly like mine. a rocket to 85 then not much. Never even considered the green spring.
Thanks for your input
J
 
jhawker670 said:
Ok Mr viper, View attachment 53566View attachment 53567 I took sled out for test run after installing weight. Heres what I found out:

Stock 22/38 gearing. Confirmed

HC Red Primary spring within spec
5.0 heel, 3.3 mid, 4.3 Tip weights

New Yamaha red dot sec spring
Dalton 48/36 cam
80 Deg twist

Machine engages at about 4700 rpm then jumps up to 8300 fast, then creeps up to 8400-8450 Rpm. Hard to compare top speed cuz it is about 34 here today and the trail was sloppy, but I think it would be about the same. Def NOT 110-120 on speedo! I took pics of the marks in the sheeves. Def not shifting out all the way. Black marks on primary are about .900 from top and secondary about .900 from bottom. What do ya think? Im surprised top rpm is about the same since i put alot more weight on it.
J
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1.)how far are you running the sled for checking with the marker on the clutch's?

2.)I disagree on the sec. spring, the red is faster then the green is in a single pipe viper, checked it multiple times with differnt set ups on radar. By adding the green your just going to make the back clutch fight the front clutch and likely keep the belt even lower in the front clutch. Get a green dot sec and try it and test it out.....

3.)I know the m10 suspension puts alot of drag on the track, if you prop up the sled on a jackstand is the track hard to turn by hand? You really should be revving a tad more rpm, but i also note the temp and conditions, so I think you have some parasetic drag going on.

running it at 34 degrees it will be down a few hp because of the air quality, so when it gets cold out and the snow firms up or gets more fluffy repeat your test and I bet your rpm will rise a bit, your speed will improve as well. Wet slushy snow creates drag, the rear clutch is torq.sensing so the more load it sees it tries to backshift which results in the belt being lower in the front clutch as well.
 
1) 3/8 mile wide open
2) i agree will you on green spring
3)I just changed slides today track is 3/4 to 1.0. def not tight.
I will leave it and run it when it gets colder and let ya know.
Thanks, sir
 
I don't understand how a red dotted secondary spring is capable of holding up and keeping up with a HC set up. Compare it to a spring from any other manufacturer from the same era, I think it is pretty weak compared to them. I think a red spring on my MM would seriously bog the sled down when hitting any amount of snow on the trail. But if it works for you, nothing is better. I went 124 mph (speedo) with a srx 700 with a hauck #5 clutch kit (free running lenght), and it had a pretty stiff gray spring. The reason I think this is working for me is that I might have a little more in the tip than the other HC set ups here. I am not a clutching guru by all means and I'm sure MrVipers set ups work better for what he is trying to accomplish, but I prefer to adjust them to my riding style. I had a HC set up with a hauck red spring @70 deg for a srx that I got up to 116 mph (free running lenght), but it overrevved, so I couldn't test what it really could do. I have bought a new helix since then, I am going to give it a try this spring. But the best part, it backshifted much like a race sled. I've never seen such backshift on a Yamaha, other than the sx/sxr race sleds in the late 90s-early 2000s. I admire and respect MrViper and he taught me alot about everything about the srx and mm. It's all in how you make the parts to work together. I do realize, not hearing to all his advices regarding clutching might bring me off track, but I like to test test test.
I even put a HC set up in my MM, with a crazy helix for that sled (50/38 dalton), because I had nothing else, so I put a red hauck spring @70 to kind of hold it back. Result? Beat all 600s on the river, including racer specials without open kit. The MM will get to 82 mph now like in 1/4th mile.
 
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Your able to use the red dot sec spring in a viper because your only using a helix thats a 48 start and a shallow 34-36 finish angle. The shallower the finish angle is in a helix the more pressure is applied to the belt via the sec clutch no matter what spring you use, so a softer spring works well and provides more top speed because the belt is already being squeezed harder from the shallow angle of the helix, plus the spring rate.
Anytime you reduce the rear spring pressure, the sled will go faster topend. Try it, do a radar run on your sled as set up, then do nothing but reduce the rear twist by 10 degrees and rerun on radar, youll find it will pick up mph everytime unless the rear spring pressure is holding your engine on peak. Which , if it is, then you need to redo the front clutch for the correct rpm.

The viper is one of the few sleds I will use the red sec spring in, red sec springs also work well in the redhead vmax engines. That helix of 50/38 isnt crazy big at all, the helix size really is just what your trying to do with the machine. I could use a 52/40 in a vmax if i wanted to set one up to do drag racing with heel clickers, youd just simply set up the primary differnt is all to run the correct rpm.

I do use the gren sec spring in most srx set ups and other set ups as well due to me using a much larger helix, so you need more spring to hang onto the belt.
 
Thank you, that was educational. It fills the white blanks of clutching, little by little. Next time I am going to give that 50/36 another try and a green dotted spring. What wrap on the helix and how many grams in the tip of the hc?
 
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Let me know what you think of these thoughts:
Seems like a steep helix is a good fix, or very heavy weights. It's all what you're trying to do. I believe the thread starter could have a sled that would both go over 85 mph and still have good backshift. Maybe not in 1000 ft but definitly in half a mile.
The only way I could see a good backshift with a red dotted sec. spring is if you had an extremely shallow helix. Seems to me like the original poster isn't going to a radar run.
 
Well I had a chance to go out this weekend to test. Temp was about 15 F. Sled pulls to 8500 and stays there. I didnt get top speed reading but I did see 95mph on speedo in loose hardpack railroad grade.sled feels snappy and wants to go and go. So Im happy! A big thanks to mrViper700 and everyone else who has contributed. Hopfully I can return the favor one day!
 
jhawker670 said:
Well I had a chance to go out this weekend to test. Temp was about 15 F. Sled pulls to 8500 and stays there. I didnt get top speed reading but I did see 95mph on speedo in loose hardpack railroad grade.sled feels snappy and wants to go and go. So Im happy! A big thanks to mrViper700 and everyone else who has contributed. Hopfully I can return the favor one day!
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glad its working better for you, keep the track on the snug side and you should see a 100mph shown on the speedo.
 
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