Just came back from a 2150 miles trip in 5 days
Rode from NC to Milwaukee and back with '83 FXRT
Some of you remember I just had my heads and valves done and had issues adjusting the pushrods.. let's say the whole trip was without "major" issues, a LOT of interstate, about 650 miles in 1 day, twice, almost all Interstate and almost never less than 70mph, sometimes 75

I left knowing I needed a complete top end rebuild.. my bike has been using a lot of oil in the last year... but after this trip I add 1 QT everytime I fill up. The bike does not leak 1 drop anywhere, so it USES it. In regular use it does not smoke... only at WOT or very hard acceleration.. black smoke. I will need suggestion on the top end rebuild.. probably in a different topic

One "problem" I had, and I have no anster to, i this: on the second day, after 700+ miles and no issues, I could head e weirdo noise at idle from the pipes... a loud CHOOF CHOOF, likie a breathing noise. I could hear the same coming out from teh oilt tank if I removed the tank's cap. That nois was there for a cuuple of days, specially with the bike hot. I did not hear it anynmore halfway back home.. at least ffrom the pipes. It kinda comes and goes... weird. I cannot think about what that could be.

The second issue I had, my air filter... 2 tabs holding the cover broke due to vibrations. 1 broke long time ago and I repaired it. It broke again... the bike does not vibrate too bad (IMHO)... I must say I had to adjust the top motor mount once I put the heads back.



Carburation/timing/valves: Look at my plugs and rear exhaust. The plugs were new... don't look too good right? I've used premium fuel all the trip, some ethanol tratment and some octane booster too every once in a while. The rear exhaus has a blue and yellow hue. It started some time ago, but now it's more evident... I seems the it's the gases from the fromt though... does it make sense? I've been playing with the carb jets, but not done yet I think. The bike runs fine, but uses too much fuel IMO, and at WOT it sputters a little... it works fine at 75/80mph and steady speeds. It backfires a little, at low rpm and not while releasing the throttle suddenly at high speeds. Maybe the valves are still a little tight as johnjz was suggesting in another topic?



and about valve adjustment... valve noise is minimal, if none at all. I even loosened the exhaust valves a little (1/2 turn) and had 2 use 10w30 and 10w40 in the last 2 gas stops (that's all they had) and the valves were not noise.

Comments or suggestions on anything?

 

I would get P/Rods adjusted correctly and the carb corectly adjusted. Check the timeing also. Then you know there out of the equasion.

 

Read this a couple of times ...

I have a hard time believing you're burning that much oil and not seeing piles of smoke. You sure it's not dumping out a vent line at high rpms, or spilling out into your primary or something? That much oil consumption and you should be leaving a trail of smoke as well as oil fouled plugs.

 

You need to do a leak down test on both cylinders , it will tell you everything you need to know about what needs attention .

 

I know it's a lot of oil there... but no, no oil trails, stains, spots or anything anywere!!
right before the trip I replace the primary chain and the clutch... there was a little oil in the primary.. stator and rotor were pretty dry and clean. Oil consumption was not THAT bad, but still a quarter every 3-500 miles instead of every 150

Leakdown test... never done one.. how do I do one? Any special tools?
Will look for info in the forum later today...

 

Hate to say it, but the tool you need is a leak down tester. You should be able to rent one. Test each cylinder at tdc. If it holds pressure, test also at bdc and middle.

 

if you think about it you can only do a TDC leak down as the valves int and exh are closed at the same time only once at TDC on the compression stroke

BUT if you are talking about unadjusting the valves / lifters to do the test than i am in, as a BDC will show the max wear on the cylinder wall as a percentage of leak - it could be as much as 20 percent loss as compaired to the TDC test -- jz

 

I have a compression tester.. and through adapters magaged to hook my compressor to the cylinders
Took off fron int and exh pushods and rear exh pushrod (the int one does not collapse enough to come out... I had to take the head off over a month ago to remove it). Int pushrod was just loose, not moving or touching the rocker.
I don't hear any air coming out from the intake, some air from the rear exh and a little from the front exh.
I just had my valves done 2 weeks ago... so don't know if it was not done right, or I f***d them after 2300 miles.
No air from the oil tank, but there's air coming out the timing hole, both cylinders
Through the spark plug holes I could see the top of the pistons... there's already a lot of build up... looks like the spark plugs above.

 

a couple of questions
Did you put new pistons and rings in the motor - Today Never use just cast iron rings Use the set that has a Moly top ring in the kit and tell the machine shop about the Moly ring - did you have the cylinders bored / honed to fit them the new pistons or what
The positive air you hear from the timing hole is from a bad ring seal < worn out and or the cylinder is way out of round -- this is the cause of the high oil comsumpion

as far as the air leaking at the tail pipes you only can hear it and not see on the test equiptment the percentage sooo its all a guess how much, BUT having said that and seeing your plug pictures i would say the crust forming on the pistons as carbon / oil crust is like small rocks and the exhaust valve seasts are not happy with what is going on < will the seats come back on there own - cant say for sure but the trip has not been helpfull as the bits of carbon have been crushing under the exhaust valves into the valve seats so

you were doing gaskets as i remember and not while the top end is off checking the complete top end of the motor has brought you to this point - somtimes doing it 1/2 way is not the best idea as what you just spent did not help you in any way -- jz

 

Johnjzjz, doh! Yes, I meant with the pushrods loose or out. I like to test the middle too, but top and bottom will tell you most of the story.

I agree pretty much down the line with what's said above. Probably time for new oversize pistons, and at least a re-lap of your valves if not outright replacement of valves, guides, etc.