Hi all,

I have done many cam upgrades on twin cams and have 2 successful M8 upgrades. For some reason this time I have a project that is baffling me. Using a Power Vision tuner, Fuelmoto push rods, Woods WM8-22XE cam, and Woods Directional Lifters. Bike idles very poorly and given enough acceleration will surge and accelerate hard. I readjusted the push rods and it improved some, but still it wants to die on initial throttle then surges. Power is strong when the bike surges and improved over stock.

I was actually doing two projects at one time and the second bike is having the same issues. Power Vision tuner, Fuelmoto push rods, S&S lifters, Woods WM8-222 cam. Same thing same behavior.

We have double checked the timing and both were on. Fuel maps came from Fuelmoto, so not doubting those. One thing to note, most of my experience has been reusing stock lifters and not doing lifter replacements. That is the biggest change in the procedures I have done before. I completed 2 cam projects before these in January, one an 96” Twin and the other a 114” M8.

Some notable symptoms, lot of pressure relieving out of the intake, oil coming out rear push rods from the top. I am wondering if with the new lifters we are not feeling 0 lash properly and not adjusting the push rods out enough? When I went to readjust the pushrods again, I backed them all off to full loose then set the engine to TDC, and adjusted the rear intake rod. 24 flats from 0 lash for Woods Lifters, but didn’t feel any pressure resistance till about 10 flats in. Let the lifter bleed down till the rod would spin then did the exhaust rod. Rotated engine to 180 from TDC for the font and repeated. I try to push down on the push rods to make sure the lifters are sitting on the base lobe, but maybe not pushing hard enough?

Is crank case pressure building up because the push rods are not adjusted out enough (for what ever reason) that the exhaust valve is not open enough to relieve all the exhaust pressure and thus back pressures out the intake? Should I try adding a few flats (3 or 1/2 turn) to the exhaust just to see if it would run any smoother and not backpressure?

I had a bike one time the jam nut backed off an exhaust push rod on the front cylinder and it left me stranded on the highway. It would cough out the intake because the front exhaust valve wasn’t opening and thus choking the engine till it stalled. Once I found the loose pushrod and readjusted it everything went back to normal.

Hoping someone has run into this before. Thanks for reading.

 

Rotated engine to 180 from TDC for the font and repeated.

Cylinders do not fire 180 degrees from each other because of the common crank pin like automotive engines do

Find TDC on rear cylinder by watching intake lifter return to base then use a straw or something soft through the spark plug hole to see when piston reaches top of travel,adjust your push rods and then repeat the same process for the front cylinder

 

Ok. After working w @fuelmoto today I discovered that the Dynojet Target Tune maps cannot be used w my Dynojet Pro Tuner even though both tuners use wide band O2 sensors. So, they sent me new fuel maps for our bikes and we are now running 100%. We made a 20 mile loop tonight w no problems. Project complete.

Fuel maps can make a big difference. Thanks Jamie and the team.

 

It looks to me like the original poster’s adjusting procedure is incorrect. The proper way would be to watch the intake lifter for the cylinder you are working on lift then begin to fall and you know that cylinder is on the compression stroke. As the intake lifter is going back down the piston is rising…carefully stick a plastic tie wrap or something similar into the spark plug hole and feel when the piston is at the top of the stroke. You then adjust both intake and exhaust pushrods for that cylinder

 

If the bike idles good and the valvetrain is quiet, pushrods are adjusted close enough..

 

I had this issue. I have a PV tuner and installed my star racing 30/30 cam and fuelmoto rods. I'm not sure if you followed the instructions from S&S for their lifters, but I know the premium lifters I used, needed to be soaked in oil overnight. There are people who don't do this, but to me, I feel a noticeable difference. My issue was mainly that I needed to keep my lifters at a little more than zero lash.. and for longer. I gave each one the night to bleed down, also giving my rods a few extra turns to make sure they were good. I loosened the rods and put them a turn or two past the 0 lash requirements. It's not going to hurt anything in the top end to have them a little tight, unless your trying to race and need your RPMs exact. I personally contacted Dyno jet for my maps. Not that fuel moto isn't reliable, I just have blow performance exhaust pipes and the 30/30 cam is very aggressive. They were also able to take a snippet of my bike log, and tweak it to help AFR. I'm not sure what bike you have, but mines a 114 M8. Best thing to do, even though it's a pain, annoying and redundant, double check you bled your lifters down, you can double check the TDC placement by using your fingers to feel their lowest points, but honestly,the best way to make sure you have your rods adjusted correctly, it to remove the timing cover and verify your timing marks for front and rear TDC and verify your cam matching up visually. I know it's stupid, but you may want to double check pushrod placement thats written on them saying ,"intake &exhaust" because it's easy to mix them up and their lengths are actually different, readjust your rods to give them a little more stiffness and try contacting DynoJet for a PV tune that fits the bike models cam and exhaust. Like I said, fuel moto is good, but they may not always have the most up to date map for the bikes setup. A GOOD MAP MAKES ALL THE DIFFERENCE! Make sure your PV tuner is up to date through your computer, If Youre still having issues after giving it time to run, you may want to bring it in to have it ran through it's heat cycles, so the problem can be pinpointed.

​​​​​​The oil coming out of the top of the push rod, sounds like you might have dislodged or pinched your o-ring when you put your pushrod cover back on. I've done this before with the wrench trick, because I didn't have the pushrod tool at the time. You can accidentally pinch the o-ring and it can cause it to cut into the o-ring. Either way, good luck!

 

It never ceases to amaze me how some people will spend the $$$ on performance parts then cheap out and go with a half assed tune and never realize the full potential.

 

He solved his issue Feb 2021

..... Ok. After working w @fuelmoto today I discovered that the Dynojet Target Tune maps cannot be used w my Dynojet Pro Tuner even though both tuners use wide band O2 sensors. So, they sent me new fuel maps for our bikes and we are now running 100%. We made a 20 mile loop tonight w no problems. Project complete....

 

Timing dots?

 

It is not necessary to quote the entire post when you answer.....