I have just completed 100 trail miles on my P650 with the black secondary EPI springs installed. Even though I purchased the red primary, I decided to try this configuration first and see what the results were before instaling the primary red spring. I am so far very happy wih the black spring, it turns the 26" ITP589's with a lot more torgue with no hint of belt slippage on hills, mud and towing which is what I was after. The following is the spec for both the standard spring and the EPI replacement:

Stock: 90lbs and 195lbs @ 21/2" and 1 1/4"
EPI : 115lbs and 220lbs @ 21/2" and 1 1/4" (PN KSS3)

There will be higher engine speed and a lost of top speed with this set up but this is insignificant compared with the results achieved. I probably will not installed the red spring. Thanks to those that have brought this topic up, I am very satisfied with the results.........MJSTX

 

MJSTX...I am going to order the red and black spring from EPI today. From what I read here, the black spring is what I am looking for. I would also like to be able to come out of the hole harder and that is why I want the red spring. Why are you not going to use the red spring?

 

Hello,

Is there a web site for EPI?

Thanks,

IronBear

 

http://www.erlandsonperformance.com

 

Iron Bear...The springs are not on the EPI web site. I ordered their catalog a while back and ordered the red and black spring for my 650 today. I also plan on modifying my muffler on Friday.(I am going to do the same thing nyroc did)...and maybe one of these days, when it is available, I am going to get a cdi box from Diamong G (1BEARMAN).

 

Ironbear, here is some info for you about Erlandson Performance. Their phone number is 218-829-6036.

Here is the part numbers for their springs.
Secondary spring-Black-------part no. KSS3
Primary springs--red---------part no. DRS12
orange------part no. DRS13
yellow------part no. DRS14
purple------part no. DRS17
orange H.D.-part no. DRS15
green-------part no. DRS16

Hope this helps.

Encore 454, I did the muffler mod on Saturday. I drilled six 1/2 inch holes through the four baffles and cut the spark arrestor out of the end cap, making the exhaust outlet 1 1/2 inches in diameter now. If you are going to use your 650 for hunting, don't plan on sneaking up on anything if you do this mod! Also, you need a 1/2 inch drill about 18 inches long to do this. I noticed I have more bottom end now that I have done this mod.

 

Ironbear...I talked to the tech guy at EPI and he told me the red spring only brings the engagement up about 500rpm...

Mastrblastr...A lot louder? Think I should drill smaller holes? Or maybe just 4 holes instead of 6? If you were still stock would you do it over?

 

Encore, If my quad was still stock, I would do the mod again. I actually like the way it sounds. It is way throatier now. If you are concerned about noise, I would still drill the six holes like I did, but maybe leave the spark arrestor in the end cap and try it that way first. I didn't think of it when I took my arrestor out, but if a guy is careful with a die-grinder, you could get the arrestor out without wrecking it. That way, if you find it is too loud, just weld it back in.

Alltoys has access to a dyno, and says he got a 10% increase in horsepower with this mod alone. I sure noticed it as soon as I took mine for a ride after I modded it. Good luck with your mod!! It is a pretty easy way to gain about 5 horse.