So, after the insides of my stock exhaust on 2002 foreman 450s let go and started rattling, I purchased an MPRB slip on after market exhaust and installed it a few weeks ago...
Let's just forget about the "slip-on" bit - I had to take it to an exhaust shop and get the inlet enlarged by 0.05 of an inch to get it to "slip-on" to header pipe..
Then the mounting instructions were completely wrong...said to discard the OEM spacers - ahh..no...you either use the spacers or have to invert the mounting tabs to get it to clear the shock...
Then it had an air leak at the exhaust to inlet pipe connection - all they tell you to do is slip the pieces together and use a supplied spring to keep the exhaust and inlet pipe together...ahh, again, no...you need to buy some Exhaust goop and ensure that connection is air tight.
So, after all that nonsense, I take it out for a test ride...
Bottom end power is fine...actually feels like a little more grunt..but I lost at least 10 km/h on my top end...I could hit 60 km/h no problem with the stock exhaust, now I am lucky to hit 49 km/h. FYI, I do have 26" zillas on this thing, so I know that saps some top speed from stocker tires, but still...
You can hear the motor winding out, but it simply does not get back up to top speed any longer...
Before I check the spark plug, anyone else experience something like this with an aftermarket exhaust?
Yes, I will eventually cut open the stocker and repair it, but wanted to get this thing going asap and bought the MBRP exhaust...
Thanks for any insight.