99 Vmax SX 600 Clutching setup

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befarrer

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I picked up this 99 Vmax SX with the 600 triple last spring. I got 1 ride in to see how it performed before the snow melted. The biggest issue I had was Clutching, it felt smooth, but overreved, I could get over 9500rpm at full throttle at any speed, I kept driving at reduced throttle to keep rpms below 8700 or so. The sled has higher mileage 14,000km, but is in great shape, spent most of its life as a trail sled by an older gentleman who didn't go full throttle. I am not sure if my Clutching is due to worn springs, or incorrect setup. The sled has a 136 track extension with 1.25" lugs I think. I just inspected the clutches, they are not worn or sticking. But it has the following setup:

Primary has 8DG-00 weights with a rivet at the top only, and an all orange spring. Secondary has a Bender 9960 helix (51/47), and a black spring with 1 pink spot, in the #9 position on the helix and #1 hole on the clutch.

I am fairly new to Clutching, but I think my fault lies in the secondary clutch. My riding will be local central Alberta, no mountains, trail, field, and ditch riding. There isn't much info on the setup page for 600's, other than some mountain max sleds, which would have different gearing, and I'm assuming the longer more aggressive track makes a difference over stock too.
 
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i would start with a new primary spring 1st as they do get weak over time. then i would add tip weight to get it down to desired rpms. these sleds over rev from factory and needed adjusting back then. sounds like some one has done some clutching to it as the rpm's you are seeing is what one with tripple pipes would usually tac out to.
 
Would I be fine setting up primary clutch to factory settings? Even though it has a longer and grippier track.
 
if they put smaller 8 tooth drive sprockets in, you could go that way but might still have an over rev. done a few sleds that we went longer with the smaller sprockets and had no serious clutching issues.
 
Spring with pink dot is for a four stroke and not the right one especially at 100 wrap. It should have a red dot on it at 80 wrap. 6 on helix and 2 on the secondary.
 
Clutching this is hopeless onless you gear up some to compensate for the gear down due to smaller sprockets.
 
smaller drivers where the easy way to get the clearance on those for the taller lug and had to be done for studding with the tall lug as the 1-1/4" ripsaw did leave rubber on the front cooler fins on my sx500r with a tight track on the stock 9 tooth drivers.
 
Here is what we usually did to the 99 SX600, Single Layer head gasket, bore the silencer, notch the read stoppers. Stock Jetting, with stock needle position, pilot screws at 1 3/4,set fuel levels at 14.3mm. Then we clutched the sled with 8AB weights with 2.4 G in both holes, 15mm rollers, G-S-G primary spring with 1 engagement shim. Secondary 48/43, green secondary spring set at 80 and make sure you ran an 8DN belt.
 
Was asking because I’ve done Turk’s clutching setup and just need to drill the exhaust and thin the head gasket. Will see how it performs on the trails this winter. I was a little concerned that the 8CA weights may be a little aggressive for trail riding so good to have another proven option.
 
The track lugs measured at 1-1/8" not 1-1/2". I'll start by ordering both new springs, set up secondary to stock and go from there. I'm going to change the chaincase oil, so I'll pop the cover off and see if gearing is stock.

What should my target RPM be for clutch engagement and max RPM?
 
max rpm should be 8500 rpm. stock engagement was 4000 rpm according to the spec sheet in the tec pages.
 
With all this info, and doing some research, I may wait until the snow flies, play with my secondary clutch spring positions. I can't remember my engagement rpm, but it didn't feel incorrect, but I think my secondary spring is stiffer than stock, but I don't know what brand it is. However, my secondary spring is much tighter, and had 100 degrees preload, so I may try a lighter preload for now. There is no snow so I can't test anything right now.
 
befarrer said:
With all this info, and doing some research, I may wait until the snow flies, play with my secondary clutch spring positions. I can't remember my engagement rpm, but it didn't feel incorrect, but I think my secondary spring is stiffer than stock, but I don't know what brand it is. However, my secondary spring is much tighter, and had 100 degrees preload, so I may try a lighter preload for now. There is no snow so I can't test anything right now.
Click to expand...
Report back
 
Still no snow, but I popped the chain case apart and I have the stock 21/39 gearing, and I have 9 tooth drivers. Checking engagement rpm, in the garage on concrete, I'm just shy of 5000rpm, so my orange secondary spring must be stronger than stock.
 
You mean orange primary spring? That sounds like a hauck orange with a 55 kg pre load and a 135 kg total force. This is overkill for a sled like this unless you have some really weird clutch set up. The good news is that you can get it down to lower rpms now, that you have the stock gearing and 9 tooth drivers.
 
Probably the Bender orange which is too stiff, but not as stiff as Hauck orange that was intended for drag racing only.
I would go with the stock style primary spring and then use rivets in the weights to fine tune if necessary.
Leave gearing alone at 21/39
Given the miles, you should also inspect the surface of the weights for notches/grooving.
 
MrSled said:
Here is what we usually did to the 99 SX600, Single Layer head gasket, bore the silencer, notch the read stoppers. Stock Jetting, with stock needle position, pilot screws at 1 3/4,set fuel levels at 14.3mm. Then we clutched the sled with 8AB weights with 2.4 G in both holes, 15mm rollers, G-S-G primary spring with 1 engagement shim. Secondary 48/43, green secondary spring set at 80 and make sure you ran an 8DN belt.
Click to expand...
Nice tweaks. The 8ab and 8ca weights were great.
 
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