Cooling system question

[jsledder]

So, I've got 2 of the 97 700 motors that I've converted to run on Mikuni rack's and have been told that I need to get the proper cooling to the motor. Basically I need to put a fitting on the back of the water pump and under another under the thermostat, and connect them with a hose as well as adding a thermostat. Got the parts, started tearing one down and I see there is a plug on the opposite side of the water pump that I'm not exactly sure why it's there and if I can use this port as my bypass going up to the thermostat. Looking at several different years of parts diagrams and I don't see this plug, but here's an actual picture and both motors have them.

 

[Jay]

I thought that was a drain plug for the cooling system? at least thats what I use it for. Why do you need "proper" cooling and a thermostat? What is "proper" cooling?

 

[X2Freeride]

Yep that would be a drain. You can also use it to bleed air out of the system. The thermostat thing isn't that big of a deal ever rack crab twin I have ever had I have run without a thermostat.

 

[jsledder]

Well, I was going to take them over to Indy Dan and have him tune them up, we just can't seem to get them dialed in just right and were just going to take them to someone whose probably done thousands. He told me this would make a big difference in how the they run on the bottom end, and to get the proper cooling to it before trying to get them dialed in.

Don't tell me I just fell for a muffler belt trick and wasted $105 on an overpriced Polaris hose and thermostat (that doesn't fit)!!!

 

[X2Freeride]

Well, I was going to take them over to Indy Dan and have him tune them up, we just can't seem to get them dialed in just right and were just going to take them to someone whose probably done thousands. He told me this would make a big difference in how the they run on the bottom end, and to get the proper cooling to it before trying to get them dialed in.

Don't tell me I just fell for a muffler belt trick and wasted $105 on an overpriced Polaris hose and thermostat (that doesn't fit)!!!

I run a little bit bigger rear cooler on most of my sleds, That seems to keep the temps more consistent so you dont see the radical ups and downs. Only thing about running without a T stat you have longer warm up times. It may help you out with the stock cooling system some what... But it shouldnt still have been that bad to tune. Just out of curosity what jetting specs are you running in the carbs? what needles, pilots, mains ect...

 

[jsledder]

These both have full length wide U-Coolers, SLP Pipe/can.

Right now we're running SLP's specs and ATACC's - 460/470 mains, 8DGY1-57-2 needles, 45 pilots. 1 out on the air screw and 1.5 out on the fuel screw. They run great after 1/4 throttle. 50 pilots make it worse, needle clip works best in the 4th slot. Lots of gas in the air box.