my praire 400 would go 45 last year,this year i have a hard time getting it up to 40 and the only thing i changed was i bought a set of mud lites that are the same size as stock ones that were on the bike.anybody have any ideas on mods that i can add without spending a fortune to gain some of my get up and go back?

 

Brian look at the air filter and make sure it's clean. When I had my 400 I jetted it and K&N it when I up the size of tires and I didn't loose power. Also check your plug if you haven't use your bike much.

 

i put a new plug and cleaned both my air filter and carb.

 

what year do you have i had a 97 , 99 early years could use a little more tension on the secondary spring thats a97 or 98 are 99 ran 54 mph all the time with 57 top speed wife driving

 

it is a 97 with 2000 miles on it.a friend at work said he put a white spring in his polaris and it made a difference,so i called dealer up and asked him about the white spring and he said he did not know of anybody adding one to a kawi 400. has anyone out there added this and does it work?

 

please help i would like to fix problem by the weekend.

 

Brain you could try epi or daltons for a spring on your 97 when ihad mind i just adjusted the preload on the secondary the rpm would drop off at top end I put 2 more pounds of driven tension on the secondary and it helped but check out a different spring it should work better also check and make shur the rear brakes are not sticken the foot peddle rust up in time

 

Did you fix it? I got mine out this summer for the first time in months, and my rear brakes were stuck, they dont feel like it when using the lever, but go behind the bike and pull on them and they released. I went with 26" lites, and only lost about 5MPH top end, I can still go 51MPH.
Another horror story, a friend of mine stored his bike every winter, and some mice made a nest in his airbox. He got them out after it wouldnt run, but then his bike wouldnt go as fast, they also made a nest in the belt housing, and all that junk was slowing it down. might be time for a look see.