93 evo rebuild help
#1
93 evo rebuild help
I just rebuilt my 93 fatboy. recentley after breaking the motor in, when i shut off the bike the engine makes a clunking noise on its last stroke before the engine shuts off?
im not sure if the push rods need to be re adjusted or maybe the timing is off. anyone have any ideas?
im not sure if the push rods need to be re adjusted or maybe the timing is off. anyone have any ideas?
#3
agreement
A noise, my first thought is a pushrod but if this is the case then you have a valve hitting the piston not good...I concur if you can rotate that tire listen for the thud or noise again. I have never experienced a valve sticking I have unfortunately had a valve hit a head....it was a painful learning experience.
#4
If the motor has been running for a while valve train & pistons hitting would be unlikely . You hearing a mechanical metallic noise or a motor " knock " like when you lug it to high a gear ? Also what your eng specs? comp & cam lift ? High compression and a big cam doesn't play well with some gas out now so you will get ign. knock like dieseling with too much advance when shutting down . Back the timing off a few deg and see how she runs , you may be surprised .
#5
the noise is like a rubbing clunkin noise. I rode it in a fourth of july parade this year and after it was done i noticed the noise. It looked low on oil, so i added oil to it and started it. the noise was still there. i parked it in my shed and shut it off, and upon the last stroke of the engine before it shut off, it make that rubbing clunking noise reall bad, almost like the crank was free falling to the bottom of the case. That is the best i can describe the noise.
As for the engine spec:
93 80" evo
10:2:1 compression
.500 lift
evo 527 cam
adjustable push rods
Kenith black pop up pistons
.500 lift head spring kit
Crane valve kit
stock CV carb and intake
Single fire ignition
I run the bike on 93 octane only
As for the engine spec:
93 80" evo
10:2:1 compression
.500 lift
evo 527 cam
adjustable push rods
Kenith black pop up pistons
.500 lift head spring kit
Crane valve kit
stock CV carb and intake
Single fire ignition
I run the bike on 93 octane only
#6
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#8
What's your plugs & pipes look like ? A lot of black soft oily feeling soot around the exhaust ends and does she puff a bit when first starting ? I've had a few engines with high end piston set and the hard chrome moly rings instead of the plain cast iron that didn't fully seat till over 2500+ miles , bike's were ignorant as hell till then .
Have you tried a leak down test just to be sure everything is seated ? And maybe take a look in the primary for that clunking noise ? I don't know where else to go with this so start at the basics and just go through the steps one at a time that way your aren't guessing and the bikes really needs a good once over after some break in mileage after a major anyway , I always catch things missed of forgotten about during the big stuff .
Still sounds like a timing issue with those specs and components , I'm running 11-1 @ 93" dual plugged in my shovel and had to take my timing down to 30 - 32 degree's to kill the gas detonation knock and that sound like what your is doing . Who's ignition system ?
Have you tried a leak down test just to be sure everything is seated ? And maybe take a look in the primary for that clunking noise ? I don't know where else to go with this so start at the basics and just go through the steps one at a time that way your aren't guessing and the bikes really needs a good once over after some break in mileage after a major anyway , I always catch things missed of forgotten about during the big stuff .
Still sounds like a timing issue with those specs and components , I'm running 11-1 @ 93" dual plugged in my shovel and had to take my timing down to 30 - 32 degree's to kill the gas detonation knock and that sound like what your is doing . Who's ignition system ?
Last edited by TwiZted Biker; 07-09-2011 at 03:00 PM.
#9
One thing to check, remove the derby cover and see if there is any movement/play in the clutch basket back and forth. This would check the nut torque on the engine and the clutch and primary chain tension. Would also save your oil.
If you don't care about the oil, pull the primary cover and check the torque on the engine and clutch nuts directly.
A clunk on shutdown sounds like something is continuing to rotate once the crank stops. A rubbing clunk maybe primary chain. It is the only thing that rubs something on purpose (the tension block).
If you don't care about the oil, pull the primary cover and check the torque on the engine and clutch nuts directly.
A clunk on shutdown sounds like something is continuing to rotate once the crank stops. A rubbing clunk maybe primary chain. It is the only thing that rubs something on purpose (the tension block).
#10
the exhaust is sampson short shots. the black at the end of the pipes doesn't appear to be sticky, just thick. Plugs are E3 spark plugs from Jp cycles. The ignition system is crane cams and wired to be single fire which also came with a adjustable ignition module under the seat to chane RPM limits and cam curve.
The only thing that had leaked was when i first started the bike. The front most pushrod tube was spraying a little bit. I took the spring cover off of it and found that the o-ring was not seated properley, other than that i have not found any leakage.It only was puffing smoke when i first started it, there was so much that i could not even time the bike yet.
The only thing that had leaked was when i first started the bike. The front most pushrod tube was spraying a little bit. I took the spring cover off of it and found that the o-ring was not seated properley, other than that i have not found any leakage.It only was puffing smoke when i first started it, there was so much that i could not even time the bike yet.