While messing with my SP, I realized the speedo uses a simple hall effect sensor "counting" holes in the RF brake rotor. Adding or subtracting holes by the same percentage as your tire change will get you much closer to actual.

I figuring the stock are nominally 25" (optimistic) and my Titan's are nearly 27" depending on inflation, I get an 8% increase in diameter.

There are 23 holes in the OEM rotor. Since we can only add complete holes, I drilled 2 more (25 total) for a 8% increase in speedo reading.

Now instead of running 54-56ish tops, I run 58 to 60 and even 62??? on a very slight downhill.

You results may vary...[img]i/expressions/face-icon-small-cool.gif[/img][img]i/expressions/face-icon-small-tongue.gif[/img][img]i/expressions/face-icon-small-wink.gif[/img][img]i/expressions/face-icon-small-tongue.gif[/img][img]i/expressions/face-icon-small-cool.gif[/img]

 

I have read several of your post and replys now either you are a polaris mechanic or you have a P.H.D. in POLARIS applied science and physics.You have forgotten more than I will ever know about Polaris.I do like your advice It always sounds good, hey thanks for your replys and post cant wait for the next one.[img]i/expressions/face-icon-small-happy.gif[/img]

 

I guess I like underdog/misunderstood foundations like Harley's, GM diesels, and Polaris ATV's. Properly set up, they can KICK ***!!!

To add 1 hole for 26s and 3 for 28s SHOULD get you there.

I have NOT checked for accuracy, but feel it is likely every bit as accurate as the factory calibration also figuring tire pressure makes a big difference as well.

 

I to take mine apart every time I get a chance Ive owned 3 POLARIS atv's and just had to see what made them tick.Hey you replied back to me a few days ago about the douglas .190 wheels and the rear hubs being machined down a little bit for the studs to extend out a little more.I called Douglas wheel company and talked to about half a dozen people before I got to a design and product guy who belive it or not listened to me about there wheels and POLARIS A.T.V.'s.His reply was that Douglas knows there wheel wont fit and that they are going to do some wheel retro-fitting just on polaris 500 sportsman to try and come up with a fix for the wheel problems.I thought at least they listen! I even told him about your reply to my post and he said most of there fixes come from just average guy's who wont take no for an answer and take it on them selfs to slove a problem with there machines.I was told to call him back in a couple of weeks and he would let me know what they are planning to do to resolve this problem.

 

Ted was the guy I talked to at Douglas. He said he was disappointed in their QC and these wheels shouldnt leak.

I bought first pair from Tread Depot. NEVER again. I fixed the leak with JB Wled because I had no intention of changing both tires. When I asked to echange for a FIRST quality, they said I had voided my warranty.

Basically, Ted cut me a really good deal on a special pair for the rear.

If they would cover the seam with a nice bead of silicone, all would be well.

If they'd weld them better, would still be best.

BTW, Polaris' fix is to use an accessory lug nut of the acorn style. That way you won't see that you are only getting a few threads...

 

TREAD DEPOT is who I talked to first also over in ATLANTA all they would tell me was to buy longer studs for rear not very friendly guys to talk to on the phone.There reply was do you want theme or not I said not! glad I did at this point I will talk back with DOUGLAS in a few weeks and will keep you posted.Thanks for the heads up about TREAD DEPOT even though I have all ready got my fill of them.