question for BC Dan - Snowmobile Forum: Your #1 Snowmobile Forum

steepndeep · 07-05-2012, 10:29 PM

I see that you are running a 2008 600 155" RMK. I have a 2008 600 155" Shift with stock gearing and clutching. After another post where you gave suggestions on clutching and gearing for another member, I was curious as to your recommendations for gearing and clutching for my Shift.

**BC_Dan** · 07-06-2012, 01:06 AM

I really like how the 600 was set up from the factory, gearing and clutching seem to work really well for me on my 08. When the primary gets enough miles to require rebuilding, I will adjust the primary sheave-to-belt distance, as my clutch is pretty far out. That's about the only thing I would change. I'm running the stock 10-58 weights with the stock 140/330 spring. That spring gives me a soft engagement, which helps keep the track from spinning and trenching. My full shift RPM is about 8250 and the engine holds that rpm when I'm climbing, right up to the point I get stuck

I ride mostly 5500 to 8000 feet.

As far as sprocket ratio, my sled has the stock 19/41 sprockets and I have not seen a need to change. It seems to turn the track fine. I'm not expecting to set any land speed records any time soon, though. I don't like the 2.4" paddles on that track, the tips bend over too easily and the back end gets really squirrely when the snow ices up. My 700 has the tips shaved off, making the lugs a bit shorter, but the track is much stiffer and doesn't spin out in ice near as badly. I like that.

You may gain a bit of performance by replacing the springs if your springs have a lot of miles on them. What's your sled doing you don't like? If you have specific issues with the sled, we may be able to narrow down some possible solutions for you. Is your Shift carbed or EFI? that will make a difference, as well.

steepndeep · 07-24-2012, 12:05 AM

Sorry, I overlooked your quick response but I was out on forest fires and missed it. I'm running the carbed shift and have been pretty happy with it except when I back off the gas slightly and then get back on it. It seems to not be back shifting properly and I can't get the RPM back up (hangs about 7800). If I let completely off and them get back into it, then they jump up to about 8200. Can't say for certain but I've got about 1800-2000 miles. My riding is in your approximate range 7000-9000'. Bought machine new and everything is stock.

**BC_Dan** · 07-24-2012, 09:47 AM

One thing I did to my carbed 600 was to block off the hoses from the VES valves to the solenoid. That seemed to improve the throttle response. The solenoid opens at a pre-set RPM, which aids emissions but takes away the "variable" part of the VES. I kept the stock system intact and used a couple of short hoses. I plugged one end with the shank of a bolt and clamped it to the valve. It's easy to put back in place; just remove the hoses and reclamp the stock stuff. You have to leave all the wiring intact to the solenoid, the computer uses it. Dang computers. They should ask first.

Stay safe on those fires. We've been pretty good so far, bunch of little stuff but nothing major. <whew>

steepndeep · 07-24-2012, 11:17 PM

Does the carbed version use a computer?

**BC_Dan** · 07-25-2012, 12:05 AM

it's not the same as the EFI version, but yes, there is a computer. You will see hoses going from the VES valves to a solenoid on the left side of the engine bay. The solenoid takes input from the electronics and opens at a specified RPM, so it acts more like an on/off switch than a variable valve. Bypassing the hoses makes the valves variable again, which seems to help. You don't have to remove any of the wires or hoses, just disconnect the hoses, plug the ports in the cylinders, and see if it helps.

Some guys have gone to a different color spring in the valve, as well. I would look at the springs inside the VES, on all of my IQ sleds, the mag side VES valve spring opening is directly under the drain for the headlight assembly. The water that gets in the cowling drips right into the valve, rusting the valve out. If there's an discoloration around the top of the valve, you can be pretty sure the spring is rusted. If that happens, plug the hole in the headlight assembly and drill a different hole in a slightly different location so the water that gets in there can drain elsewhere.

steepndeep · 07-26-2012, 12:31 AM

Thanks a bunch, I'll give it a try. Been building machines for the Grandkids. 1987 Indy 400, 1989 trail 488. 1989 Indy 500, 1991 Indy 500, and a 1979 Yamaha Enticer 250. Hope to have all of them going by first snow.

**BC_Dan** · 07-26-2012, 09:20 AM

Good on you! Gotta get 'em hooked early so you have riding buddies later

Grandma must have the patience of Job... sleds everywhere!! I'm fortunate, my wife tolerates my addictions pretty well

Does she roll her eyes a lot while shaking her head a little??

steepndeep · 07-27-2012, 12:21 AM

Lately, almost everytime that she's been out to the shop it's been "Did you get another snowmachine?" She has her addictions and I have mine, so she doesn't complain too loudly. Should have 7 running machines by winter. Registering all of them will probably require a bank loan.

**BC_Dan** · 07-27-2012, 09:52 AM

The things we do for our family

Oregon is awesome, it only costs 10 bucks a year to license a sled. It makes it pretty easy to keep up on the licenses!

I had 9 sleds all running one time... put 'em in the yard and started 'em all up in the middle of summer. I'm sure my neighbors think I'm nuts. They're probably right

steepndeep · 07-28-2012, 12:20 AM

$32.50/sled here in Idaho. For a while I was living in Wyoming and my wife was in Idaho, so I was having to purchase stickers for both states. If you ever get this direction drop me a line and may we can hook up and I'll show you some Idaho riding along the Continental Divide.

**BC_Dan** · 07-28-2012, 09:16 AM

Bring your shovel, I have been known to get stuck once in a while

steepndeep · 08-01-2012, 10:55 PM

My philosophy has always been "If you're not getting stuck, you're not learning" and I've also been known to do a lot of learning on some rides. Have a good summer.

white lightning · 08-02-2012, 11:28 AM

Its amazing how some states are cheaper over the other - in NY, if youre a snowmobile club member, to register the sled is $45, non-club member will have to pay $100. Ouch - WL

white lightning · 08-02-2012, 02:11 PM

Quote:

Originally Posted by BC_Dan

it's not the same as the EFI version, but yes, there is a computer. You will see hoses going from the VES valves to a solenoid on the left side of the engine bay. The solenoid takes input from the electronics and opens at a specified RPM, so it acts more like an on/off switch than a variable valve. Bypassing the hoses makes the valves variable again, which seems to help. You don't have to remove any of the wires or hoses, just disconnect the hoses, plug the ports in the cylinders, and see if it helps.

BC DAN, interesting concept - why did Polaris use the solenoid instead of an exhaust pressure like the way it was before solenoid was added? When I had my first '99 XCR8, I was told by unpluging the TPS, that the sled would run stronger - Ive tried and didnt noticed any of the differences. WL

**BC_Dan** · 08-02-2012, 05:21 PM

I'm not sure, but with the solenoid, the ECU can more finely tune the injectors to run on the lean edge to reduce emissions. That is always the weak spot in a 2-stroke, they run a lot dirtier than a 4-stroke will. And EPA demands we have clean air.

dhridenh · 08-02-2012, 07:48 PM

i hate the epa

white lightning · 08-03-2012, 09:27 AM

Thanks BC DAN.