The starting problems start!

The part i took out for my hot motor, cold starter test was the starter motor and starter idler gear/ limiter assembly.

I finally opened the starter clutch cover and the starter clutch set looks discolored as if it was overheating. The starter bearing looks fine and rotates and the bearing in the starter clutch set looks good and is rotating but the discoloration is disturbing. I will get a new one tomorrow to test. I cant think of what it could be outside of the starter, idlers gear and starter clutch.

Will update tomorrow.
All starter clutches with 500 miles on them will have the blueing in the metal. They do run hot because they are slipping when the motor is running and gripping with the starter rpm is higher than the motors, like when starting. As long as it turns one way and not the other your fine. I was alarmed as well but after i swapped a friends that was also discolored, and bought a new one that discolored later, i learned thats just what they do.

PLEASE let us know tomorrow!!! together we will find and fix the problem! Viperam when we talked mentionned that he tought it might be an injector locking up open when we shut off the motor and hydrolocking the motor, in my case i tried turning the motor over by removing the 10mm allen acces bolt in the cover when the motor was hot and wouln not start and it turned as easely as it does when cold, so i dont think thats the problem. Im still convinced the problem has got to lie in the starter cover/gears/clutches mecanism

This is really annoying as my busa powerplant is in a t-rex worth 50k (Campagna- Fun, Style, Performance) and having to bump start it is not an option.

Are you saying you replaced a the bolt on the starter clutch "cover" and instantly your bike would start fine? Venting that cover would have no impact on the problem. Im confused why doing that test, instead of removing the spark plugs would eliminate partial hydrolock putting extra strain or drag whe the engine is nearing the top of compression during rotating.

After listening to both of our bikes, it sound like the engine is turning over fine nearly the entire rotation and when it gets to the last of the compression it strains to get above top dead center and when it does it drops fine till the next piston tries to get to tdc.

If a gear, bushing, or bearing tolerance was allowing and idler gear to bind between the starter and the starter clutch, being they are perfectly machined and round, you wouldnt get the symptoms we have. You would get an immediate bind, that is has no reguard for what degree of rotation its in. It would kink and lock up. Not drag really hard for 90 degrees, release and then bind up again, prefectly consitant, and repeatable only when hot. It wouldnt work perfectly normal cold with absolutely NO signs, and when barely warmed up act this bad. There is no middle ground. it doesnt gradually get a little worse depending on how hot it is. Its working, or its dragging. ON-OFF

Believe me, i convinced myself and the 5 shops convinced themselves it was that assembly, but after replacing ALL of it, EVERY FUKIN part of it at once, and swapping with a known good bike and eliminating it. Only then, did this explaination make sense.
 
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no i didnt replace the bolt i simply inserted a 3/8 ratched by removing the 10mm allen acces cover bolt to rotate the motor by hand when hot, i also tried cold and the motor turns just as well. the motor still would not rotate on the starter after i rotated it until cold tho:banghead: I will replace the injectors also when i put it back together, i have acces to an extra stock set.
 
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the fact that I can push start my bike just as easily hot, eliminates anything in the crank/engine!..in my opinion. An i eliminated the starter motor as the problem, so the oonly thing between those two is the starter clutch and starter bearing. Bearing looks good.

Tomorrow i get the new clutch and bearing and will install. Cross your fingers for me and all of us guys!!! If this does work, i dont know what to do.

Talk tomorrow night.
 
defeat, destruction and terror. FAILED FAILED FAILED!!! New starter clutch and same problem.

I think i maded it worse because when i took it all apart yesterday BEFORE gedtting the new clutch, I put it back toegther quick toi show a friend that was helping how it still starts when cold and for the first time,. it didnt start while cold. Acted as though it was hot!!.... hhhhmmmmmm. Maybe the bolt on the starter clutch is not tight and allowing it to spin.... lemme make sense of this.... .i am gonna use this engineering degree... FINALLY

stay tuned.
 
Ok... i am back to square one which is a good thing in my case. The bike now start while cold (only). I cleaned out the starter motor, reassmebled and that helped however the new starter clutch made no change.

Open to sugggestions.
 
That was the first thing i tried. Swapped with a good one and no difference. Also eliminated that asa the culprit by putting power direct to the starter motor. Works while cold. Doesnt when hot.
 
have you tried swapping for antother set of injectors? i know viperam will and i will too when i get my motor back together.
 
what do the injectors have to do with the hot starting? I have another set I can try.

How do I test the starter is working at optimal performance?
I read some other forums talking abbout the temp sensors to the airbox and engine case and how they can somehow get swapped. what are your thoughts there? I will test that this afternoon.

In all honesty, my bike does feel hotter that what I remember last year. The gauge is still just below half way but the heat on my legs and the frame is ridiculously hot. Strange. I hard wired the fan to always be one and no difference. Was thinking of running engine ice coolant to keep the bike cooler.
 
me and viperam where thinking that maybe a sticking injector could cause a cylinder to get flooded with fuel so it be hydrolocking, when its cold the fuel has time to evaporate and then the motor can turnover. Try this, unscrew the 10mm allen acces nut on the starter clutch cover, turn the motor over with a ratchet so you can get a feel for it. put back the nut, start the motor and let it get warm. stop the motor unscrew the nut and try to turn it over with the ratchet again, should not be harder. I also read about the temp sensor in the airbox mod, but its not our problem, since we isolated it by putting a battery directly to the starter. try it and let me know!
 
you know what i just had a flash, my busa was hot starting just fine before. The first time it did it, (remember my busa motor is in a t-rex) the t-rex has a bad design on the fuel tank, the fuel pick up is on the left side of the tank ( that problem has now been fixed) i took a long left hand curve , gas went to the right of the tank and i ran out of gas, i continued rolling and when the pump finally got gas i the motor came back alive on power, first time i stopped after, motor would not turn over.... maybe im on to something
 
I tried cranking it cold and hot when i was trying to swap the starter clutch and i didnt notice a difference unless it is really unnoticeable. ...so that is eliminated. Does that mean the injectors are okay? If the injector was bad, id think the bike would run like crap when warm too.

...i'll try the temp sensors.
 
a faulty injector can stuck open a little when you shut down the bike and let gas drop into the cylinder... letting the bike cool down, the gas evaporates or leaks down past the rings into the oil pan.... id really like it if you could try and swap yours, i cant until i get my motor back together, waiting on my parts from ape. the temp sensors wont change anything, when i tried to start with a big battery with jumper cables on the starter, the ignition switch on the bike was off , so no power to any sensors and it would not crank.
 
i think it get the concept and to be honest, when you said injectors, I was thinking of the ignition coils (spark plug boot). Getting a spare injector will be tough or expensive. Can I take my existing ones out and test them!?
 
well you could take them out and have them tested, i have an extra set i will put in my bike to test when i get my motor back together. if you get them tested , specify to the guy testing them you suspect they might stick open when hot and power is removed from them. usually thats not something they look out for in a test, just to be sure he looks out for that. usually an injector shop will clean and flow test them, thats all. i dont even know if a sticky injector will come back to normal state after a good clean up.

if i recall, im not sure, busa injectors are 380cc
 
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It does start cold now and the cause was my own fault. When i originally took the starter motor apart to inspect and clean, i threw it back together incorrectly because I was getting a new one anyway from DB Electric. WELL -They sent me the wrong one and I had to put the old one back in and it was appareant that I put the shell on wrong ie, it was not locked in place and would rotate. Cleaned it and put it back in and its good again.

I will take the injectors out tonight and clean. Hopefully there is something obvious I can spot.

Question tubor1, it an injector is leaking that would flood the cylinder, in essence creating increased compression, soooo...if i unscrewed the spark plug, that would reduce the pressure and so cancel this potential failure mode, correct?

...because i did that and no change.
 
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