ok, picked up a wrecked evo about 3 months ago. got it back together a few weeks ago. i didnt have to touch the engine started right up, i though it had an odd idle but it runs. it really likes wide open throttle, not so much just off idle, its surges when going slow in towns cant seem to make it happy.

yesterday i took the timing cover off and it is set almost at full advance. got the timing light out and set it at about 35 degrees(no more pinging) and then i set the air mix so there is no hesitation. runs better and idles sounds less odd (still no potato potato) and the surging is better but still there. it has a cv carb with a force winder screaming eagle module looks like stock heads champion spark plugs cycle shack exh. s&s cases.

would a cam make it run like that? or jetting. i didnt think its jetting there is no popping and the spark plugs look good. help

 

anyone? i just went out and started it. it started hard. but sounds better then before, the idle sounds almost normal. haven't gone for a ride, its raining.

 

Everyone is watching football! I can't answer your questions, I've never timed my bike, never put in a new cam. I just take it apart and put it back together chasing noises. It's raining in Maine? I bet that's cold rain too. Still summer here.

 

it is 60 here in maine. the sun will peak out the it will shower.

 

Carb issues? Running rich? Running lean? Old fuel? Take off carb and clean it. Could have dirt or gunk in small passages.

Has the butterfly slide air bleed hole been drilled and drilled too large? If the bleed hole is 1/8 inch or larger it has been drilled. This can cause the surging. The hole can be JB weld filled and then re-drilled to 7/64 (stock bleed hole size).

Check fuel flow, check venting of gas cap. Check float level. Check air mix screw and make sure the packing washer, O-ring, and spring are in place and in the correct order.

Trying to figure out if it has an aftermarket cam can be a challenge. Look for wrench work on the cover bolts, remove pushrod covers and see if adjustable pushrods have been used, but other than eyeballing the cam, tough call.

You can try and measure the lift but I'm not sure what stock lift is. Good luck with it, nice looking scoot. YD

 

I was thinking along these lines too.

 

Thank you for the replys. I was going to get a rebuild kit this winter anyway. can you recommend a good one? Thank you YD. It turned out nicer then I had hoped, I didnt see it all together when i bought it. I was happy when I started bolting on the tins.

 

CV performance is the best carb kit for your cv carb , as for the cam you'll you will have to open the nose cone & look , www.cvpermormance.com , Ken & the guys know there stuff & it's all made here in the USA not like the crap Hd sells you , also you need to check what jets are in your carb now with the sock eagle a cleaner you have

 

Update, since my last post I set the timing and rejetted the carbs pilot jet from a 45 to 48 and it made a world of difference. The surge is gone, I can now ride through town with no trouble. The popping and spitting through it carb is gone. so the timing was too advanced and the carb was running lean. Thank those who offered up advice.