engine problems?

[brian25]

i recently bought a 2000 banshee and it seems to have no top end? when the power band hits its like it revved out already? today it started backfiring on the left side and the exhaust is way hotter on the right? not really sure of all the mods. does have a pual turner head and pipes with fat boy silencers. and some keihin carbs dont knwo the size though. any thoughts?

[letsgetthisdone]

Could be a couple of things....

 

-fouled sparkplug

-loose or bad plugwire/caps(s)

-air leak (do a leak down test)

-lack of octane (check compression, you may need to run better gas)

-your jetting could be off (do a plug chop)

-if you have pod filters make sure they ae both on all the way

 

 

Check that stuff and get back to us. :thumbsup:

[Bansh-eman]

on top of all that above... your top end is probly shot.

[brian25]

k so i have a jet kit, new top end, new reeds, and new plugs on the way. no since in doin a compresion test now right? also what about the leak down test should i still do one? and both plugs r firing, so the plug wires r good.

[letsgetthisdone]

Once it is back together, do a leak down test before you run it. Then run it for a few minutes to burn off the assembly lube and then check the compression. If the compression is over 160psi, you need to run fuel that has higher octane than premium pump gas. Get back to us with compression numbers when its back together.

[brian25]

does any1 make this leakdown tester? and thnx for the help new here and seems like a very good forum! glad i found it.

[letsgetthisdone]

RNBRAD's leak down test(er)

 

 

 

There ya go. But DON'T cheap out on the compression tester, get a snap-on, craftsman, or a mat-co. If you don't already have a clymer, pick one up, it'll make re-assembly 1,000 times easier. oh yeah, torque wrenches too, an in-oz and a ft-lb one.

[DADEBOYRACER101]

might be top end shot or lean

[DADEBOYRACER101]

might be top end shot or lean

[2004LEBanshee]

I had a similar problem one side hotter and wouldnt hit power band when I put mine together and it turned out the pick up coil was out of adjustment.

[brian25]

one thing i failed to mention( sorry) is the last time i rode i could ride ahwile then it would die and WOULD NOT start with out having then choke on. id crank and crank untill i put the left choke on and it'd fire right up. shouldve mentioned this earlier i know sorry but been a while since ive messed with it.

[brian25]

i went a head and done a compresion test on my top end and i have about 100 on the right and 150 on the left..... that good? can i keep these pistons, or should go ahead and rebuild?

[blowit]

i went a head and done a compresion test on my top end and i have about 100 on the right and 150 on the left..... that good? can i keep these pistons, or should go ahead and rebuild?

 

 

Oh yeah! With that much variance, you have a top end problem for sure. A lack of compression will also fail to draw fuel into the engine. Some people ask twice when they bring er in for a carb tune and we tell them the top end is shot. You gotta have compression to bring fuel into the engine. Pull it down and take a look.

 

Just so I cover my ass, I should have said you must have good "ring seal". I guess you can have a blown head gasket that would cause this too but with a lack of fuel to the engine, that points right at top end.

 

Brandon

Edited May 4, 2007 by blowit

[dajogejr]

100 and 150?? Sheesh...

First off, did you use a good quality compression tester...as mentioned?

I've seen a cheapy vary PSI in a triple sled by 15 to 25 lbs per cylinder, only to get a snap on tester and have them all within 3 lbs PSI of each other.

 

second, did you keep on kicking until it didn't go up anymore? this can often take 20 to 30 kicks....

Was the engine warm or cold? Supposed to be done cold.

Hold the throttle wide open when kicking?

Lastly, does the compression tester thread into the head as far as the plugs do? (Thread depth or reach) if not...add a few PSI...

 

If this is a true reading of compression from a reliable gauge, yeah...you got big problems...new pistons and rings at the least, and a bore job....as long as something else isn't fudged up....

 

Good luck!!!

[brian25]

uhm not sure what kind of compresion tester it is....dad got it form sears.... but i didnt hold the throttle open.....i guess this will go with out saying but ima newbie not to riding but to working on the rides.