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mollydog 27 Apr 2016 18:57

The above break in is pretty good but I would add that HEAT CYCLES are also very important in the first 200 miles of operation on a new motor or new parts.

Run bike as described above ... then park it 10 minutes, let cool.
Repeat, Repeat, Repeat ... you're done!

This is how both Honda and Suzuki have done it with 30 new press test bikes at
new model launch. A few heat cycles and straight onto the track where they spent the next two days at redline! :eek3: No problems.

danimalu 28 Apr 2016 19:55

Quote:

Originally Posted by turboguzzi (Post 536868)
most likely dirt in / bad check valve letting the cases fill with oil even after a few hours.
if anything else was suspect, there's no reason the engine would stop smoking after a while.

easy to check:
check your oil level after a long ride.
check again after an overnight, if level dropped considerably, then it's a bad check valve

What do you mean with "bad check valve" ?

Jens Eskildsen 28 Apr 2016 20:49

Any info regarding the heat cycles? My bike never got hot after a rebore and new piston...At leats no heat was transferred to the oil to show an oil temperatre above normal...?

Oeh yeah, most new bikes are just about redlined on a dyno before they even leave the factory... So theres the ring seal and and heat cycle for ya :scooter:

mollydog 28 Apr 2016 23:26

Heat cycles just let new parts expand (heat) and contract (cool), allowing parts to scuff each other and speed break in due to expansion and contraction.

I figure if Suzuki, Honda and Triumph use this technique on new bikes then it should be OK for a new bike or newly rebuilt bike. I still follow break in procedures after doing heat cycles, like never running at steady RPM and never lugging the motor. I also like to snap off throttle and coast down. All this is good for a new engine, valve gear, rings, et al.

PS: you are right, OEM's do rev them to test them, check oil pressure. I've even heard they do this with ONLY assembly oil ... crankcase empty of oil.
But I didn't see this myself ... so can't verify. :scooter:

turboguzzi 29 Apr 2016 19:14

Quote:

Originally Posted by danimalu (Post 537050)
What do you mean with "bad check valve" ?

yo, lets not hijack this thread :)

study a bit your oil system from the manual. under the right side cover there is a check valve with a steel bal and spring that "should" prevent the tank draining oil to the motr when not working

open the right cover and youll see it

danimalu 30 Apr 2016 15:57

Quote:

Originally Posted by turboguzzi (Post 537134)
yo, lets not hijack this thread :)

study a bit your oil system from the manual. under the right side cover there is a check valve with a steel bal and spring that "should" prevent the tank draining oil to the motr when not working

open the right cover and youll see it


Aaa,and how i check if it's ok?

turboguzzi 30 Apr 2016 16:07

the ball should move freely, no dirt trapped between ball and seat, sealing o-ring might be squashed and old-change it . dismantle it all, good clean in solvent, remount with fresh o-ring, be careful not to let any sealant into the valve. the o-ring doesnt need sealant to seal ;)

but before you jump into this, do the very easy check i proposed you before the thread went into fresh-motor-run-in mode :)

danimalu 30 Apr 2016 16:26

Quote:

Originally Posted by turboguzzi (Post 537206)
the ball should move freely, no dirt trapped between ball and seat, sealing o-ring might be squashed and old-change it . dismantle it all, good clean in solvent, remount with fresh o-ring, be careful not to let any sealant into the valve. the o-ring doesnt need sealant to seal ;)

but before you jump into this, do the very easy check i proposed you before the thread went into fresh-motor-run-in mode :)

Thank you!

jjrider 30 Apr 2016 20:11

I saw your video on a better screen now . It's your valves seals . The way it took a few seconds after starting to start smoking , got bad , then slowly tapered away , that's the seals . Rings would smoke right away , then get worse as it warms up and have some smoke the entire time it is running . Your's quits after a minute or so right?

Too much oil would simply smoke till the oil is gone or force it out somewhere and drip on the ground . The check valve has nothing to do with it other than making it harder to check oil , even then if the valve was shot the scavenge pump will keep the motor from filling and you check the oil level in the tank as soon as you shut it off rather than waiting a couple minutes.

turboguzzi 30 Apr 2016 20:28

JJ, seen the video too:) my bike smoked in similar fashion, fixed the check valve and problem was gone :clap: It could be seals like you are saying, but it MIGHT be the check valve too. checking the valve is so easy to do before tearing into the top end that it's really worth giving it a try before, don't you think? life taught me not to be so assertive about any on-line/remote diagnosis of engine problems, even with videos :)


dani, another super easy check you can do is drain the oil from the crankcase after an overnight stop and see measure how much drains down. tell us what you found :)

jjrider 30 Apr 2016 22:52

I'll bow out , all yours ><

BTW , why have him drain the oil when he can just check the tank level right after he just ran it , and then check it after sitting overnight and see how much of a difference ? Much less work ? , it'll have to be empty to cause it to possibly smoke ,though neither of mine did when the check valves were shot , but both took 3 days to drain the tank empty , unless he forgot to install the valve completely.

Jens Eskildsen 1 May 2016 07:40

JJ, my bike did exactly what you described, after it was overfilled. It actually took a ride or two after overfilling it, before it startet to smoke.

As to the OP, the valve is around 10euro, so if you loose sleep over it, just change it. An easy way to check is to let the bike sit for a day or two, then loosen the oildrain-bolt in the frame. You actually dont need to take it completely out. If oil starts to seep, theres still oil in the frame, which means it isnt drained down into the engine, which again means the checkvalve is working. (or at least working to a point where all the frameoil, isnt drained into the motor in a day or two.)

If its bad, you should have a very hard time reading a correct oillevel when cold, but theese bikes seem like that even with the valve working.

xtrock 1 May 2016 07:58

Use a oilstick from a car, checking the pipe down to drain screw in frame.

turboguzzi 1 May 2016 08:07

tnxs JJ, actually that's exactly what i suggested in my very first reply :)

and agree with jens, they might as well drain oil slowly even with a good valve. i use both my supermoto and supermono XTs racers about once a month and I always have to drain the cases before a track session, ALL the oil usually drains down by then, it has become second nature by now.

danimalu 1 May 2016 08:54

Quote:

Originally Posted by turboguzzi (Post 537230)
JJ, seen the video too:) my bike smoked in similar fashion, fixed the check valve and problem was gone :clap: It could be seals like you are saying, but it MIGHT be the check valve too. checking the valve is so easy to do before tearing into the top end that it's really worth giving it a try before, don't you think? life taught me not to be so assertive about any on-line/remote diagnosis of engine problems, even with videos :)


dani, another super easy check you can do is drain the oil from the crankcase after an overnight stop and see measure how much drains down. tell us what you found :)

OK! I will do that!


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