i have a '99 prairei 300 4x4, it has 3,700 miles on it and just this spring it has seemed to be a little under powered, i used to have no trouble getting over 50MPH now i can just barely get over 40MPH, and i went up one of my trails that go up a fairly steep hill and it bogged down and hardly pulled me up it, and i was in low.
any one have any suggestions??
thanks

 

At first i thought it could be my belt but the RPM's bogged down, if it was slipping it should have reved up?

 

i would do a compression test on your cylinder, to see if the rings are still holding up. it sounds like it is time for a re-ring or rebuild.

 

yeh, i had thought of doing a compression test on it, my friend had a gauge and is pretty good at working on small engines.
thanks

 

how far into it should i go if i have low compression? i know rings should do the trick but while i'm in there should i do more?
thanks

 

Before you go diggin in to the motor check the easy stuff first.
If you haven't already
Plugs and filters.
Not saying that with 3000 something miles the rings aren't bad but no sense in digging any deeper than needed.
One other thing to check would be the coil and plug wires. Coils can get week plug wires get week with age. If the bike is running well just has a lose of power then it may be something easy.

 

I agree with Big Pig.. check the easy stuff first.. plugs, air filter, clean the carbs, you haven't made any mods lateley have you? Bigger tires or exhaust without a reject could cause noticable differences in power.

 

Haven't added anything, air filter is fine, new spark plug, cleaned carb, exhaust is the same as it has always been, i don't know something will show up, i just don't think it should be compression at that low of miles, my old '86 honda i had is still running and has never had anything touched on it.

 

You can check the compression but it won't tell you if its the rings or the valves.
You may just need to have the valves adjusted. Also check your ignition, coil, and plug wires. Just because it runs doesn't mean the spark is hot enough.
If your ignition is getting week and the sparks not hot enough loss of power and possible burning a valve are all thing that could happen. Just becuase the plug is knew doesn't mean you haven't already fouled it.
Hope this helps

 

thanks i will check some stuff out !