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When your bike doesnt start what do you do?

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Unconnected, Jun 1, 2012.

  1. I come from a time when things start first time regardless, however my bike does not, and as such it generally does not like starting these days as the weather is too cold, sadly i dont have a choice but to keep it outside.

    It has power, and im confident there is nothing seriously wrong with it, it just intermittently wont start, especially on cold mornings or evenings, it likes to be used between about 10:30 and 3:00 if its sunny.

    What am i supposed to do though to make it start? i live at the bottom of a gentle hill so i can push it up there and try to roll start it, but that doesnt always work as its not a very long hill and the bike cant get up to speed that well.

    Are there other tips? im considering rigging up some poly tube to my hot water and pumping hot water around the outside of the motor to keep it warm LOL.


     
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  2. Is it injected or carburated? Does it have a choke? Have you tried various different throttle positions and choke settings?

    If you do need to roll-start, you might give it a good run and jump first...

    It's a VFR400? Never owned one, myself, but from what I've seen they can be a bit cold-blooded. If you can bounce on it and get the motor spinning in 1st gear, then you might be able to hop back off and run along beside it pushing ... which won't warm the bike up, but it will sure as hell raise a sweat from you.

    You might also try a can of StartYaBastard or something...

     
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  3. Yea its a carby bike, VFR400s are pretty known to be a biatch to start in the cold, lots of people own them over in england and all they do is biatch on forums about it.

    Ive heard of start ya bastard before, how do you use it though?


    EDIT: Yea ive tried using full choke and no throttle with clutch in and in neutral with headlights off, thats whats said to be the best method apparently these bikes dont like being given much throttle to start, and prefer the choke.

    the choke cable is snapped though so i dont have the full adjustment avalible as you would on a normal bike, i pull the choke pin out from the engine with a zip tie loop, so i can only really give it full choke


    EDIT2: And what do you know, it starts now just with choke and nothing else... this is what i mean, the bike is not broken its just tempermental.
     
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  4. Talk to it nicely. Persuade it. If that doesn't work then threaten it with a replacement.
     
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  5. It's a bit hard to clutch start without a clutch cable. I've tried, but ...

    StartYaBastard is a pressure can, you get it from a SuperCheap Auto or Repco or somewhere. You're supposed to use it (on a car) by opening the airfilter above the carby, an spraying a 3 ~ 5 second hit into the inlet manifold, after hand-opening the throttle. Then you run around and crank it over - or get your assistant to hit the key.

    That would all be a major pain on a bike, but if it has a forward facing air inlet / ram-air setup, I'd be tempted to just give it couple of seconds into the ram-air without stripping anything down, and then cranking. Or spraying while the assistant cranks, or cranking while the assistant sprays, experimenting with different throttle positions and so on ...

    I don't know it would work, just a suggestion. A tune up wouldn't hurt, either. If the clutch cable's broken and the choke works off an old zip-tie, then a bit of mechanical TLC might help.

    It might also be that one or more of the rubber tubes connecting the carbs to the inlet ports has got old and started to crack. That can make for hard starting and poor idle, especially when cold.

    I just know that I see plenty of people at track days and race meetings with VFR & RVF 400s that seem very hard to start.
     
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  6. oh nah my clutch is fine i ment to say choke cable, my bike doesnt have the normal handle bar choke lever anymore, just the zip tie bodge which actually works well and makes the bike look sleeker haha.

    I plan to get the bike dyno'd then tuned and re dyno'd in the future, along with restoring the majority of the bike, at this stage i cant afford any of that though.

    I did just however get the bike going and take it for a ride around, i was practising your gear shifting methods kd, very good, i like the clutchless upshifts using the throttle, once you get a good rhythm you can really slam through the gears.

    Can you give insight though about using these techniques on an old bike like mine, is it better or worse for the transmission then using the clutch in-shift-clutch out method.? im in this mind set from my car that the clutch protects the gearbox from getting worn out between shifts.
     
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  7. you better name her, reckon might be that time of the month !! lol
     
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  8. have a little tanty until I realise the kill switch is on (off?)
     
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  9. I used to use brake cleaner instead of StartYaBastard to start my VFR400 track bike...horrid to start without it and even then it would just start.

    I binned the bike and fixed it up again and found that the valve clearances were way out. Fixed that up and it now starts first time on choke for cold days and hot days without choke.

    Maybe give the valve clearances a check...they might be a bit of a pain in the arse to do (especially the front cylinders) but can fix the issue.

    By the way 3 of my exhaust valves didn't have clearances at TDC (that's right, they were left open) which caused low compression and a bitch to start.

    Hope you work it out!
     
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  10. Done right, it's actually better.

    Heavy use and hard forces on the shift fork is bad for it. Use a little preload and let it slip across means you never need big loads, so that's better.

    Personally, I use clutch and throttle on slow upshifts, when I'm doddling around like the toothless grandfather that I am, but use no-clutch upshifts when I'm riding a little more briskly. I use clutch and throttle and back-rev on downshifts, pretty much all the time.

    A change where there is no click or clack at all might not have gone through properly. You're not sure it has fully engaged. Those are the ones that might pop out again. The ones that have a light or faint clack about them are good positive changes, and do no harm to anything. The ones that result in a deafening "CRACK!" are bad. The difference in speed between the two gear clusters was too high, and it makes damage and rapid wear possible to the dogs. A change that doesn't go through and the dogs dance across the top and grind - that's the one that will damage things. It will round off the corners of the dogs, making them ever more likely to jump back out of gear.

    You don't need big forces on the lever if you do it right, but you do need to be positive and make sure the lever actually moves all the way. Most bad changes (and false neutrals) happen because the rider made a pussy shift and only moved the lever half way. Make sure it goes all the way up or all the way down.

    Doing it the way I showed you won't hurt anything. Don't rev high then pull the clutch in and engage 1st from neutral, because it will slam in hard. Don't pull the clutch in at high speed and let the revs drop to idle, then start stamping down into lower gears with an ever louder BANG at each change. Don't try and ease it slowly from one gear to the next. It doesn't want to move slowly, it wants to slip across quickly and positively. Do it too slow and it will grind across the tops and round off the corners. Those things will hurt it.

    Common sense - it should make a quiet click or clack. If it makes a loud and horrible bang or grinding noise, you're doing it wrong.
     
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  11. What i found with the old girl and it's little cable tie bodge:

    Sometimes the choke would come out further than other times. Try pulling it out then letting it back in then pulling it out, i think it would come out about 1 1/2 cms at most. If you look, you can see where it might catch and not come out fully. Have to say, it never complained about starting with the choke so make sure it's fully on. There's no such thing as half choke either so don't bother with choke at all if you're not using it all!
     
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