Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

RVF 400 Gearbox

Discussion in 'Technical and Troubleshooting Torque' started by karti, Jun 1, 2008.

  1. I've recently bought a RVf400, it's sort've got problems finding neutral, a garage has replaced the clutch fires and they've looked at the clutch and said its pretty ok and they say it pretty straight,, not warped or whatever, but the bike still has problems finding neutral when stationary,, the garage say its to be expected from a 2nd hand bike,, and I'll just have to live with it,, also the gear movement up from 1st into 2nd is a bit more lumpy and stiff, since they've done the work.. so does anybody have any suggestions or advice?

  2. Your bike gearbox sounds about typical for a VFR/RVF. Best solution is to find neutral while you are still just rolling to a stop. Or another easier way I have found is to give it a bit of a rev with the clutch in & as the revs drop back to idle you will find it will fall into neutral a lot lot easier. The VFR/RVF use a diaphram type spring in the clutch basket instead of the usual or more common multiple coil springs & this may have something to do with it. Not sure on that though.
    For the first to second gear change, I reversed the shift pattern to race pattern (one up five down) & just simply stomp on the gear lever. No more missed shifts :) :)
    Oh -and lube up all the linkages including the shift lever to footpeg pivot. This will make a difference.
    One thing I have been meaning to try but have never gotten around to, is to try & find a lever arm with a longer distance from the centre of the shift shaft to the pivot point. This will make the shift require less force but your lever will have to travel further for the same effect. One day I may get around to it :LOL: :LOL:

  3. That is completely normal behaviour on a motorcycle gearbox.

    There are at least 2 reasons for this:

    1) The selector mechanism on a motorcycle is quite complicated compared to a motor vehicle such as a car or truck, and a small amount of lever movement is used to make a relatively large change inside the gearbox via a rotating drum and selectors which ride grooves in the outer surface of the drum.

    This mechanism has a lot of inherent friction and leverage problems, but is very effective once moving.

    2) Motorcycle clutches are almost always multiplate, and the friction inherent in this design means that even when the clutch is pulled in, a certain amount of drive force is still applied to the input shaft of the transmission. This places a reasonable amount of stress on the sliding dogs which do the gear engaging, and coupled with point 1, means that you should:

    3) Always change down gears and select neutral while the bike is still moving at 10 to 20 kmh, at least. 2nd gear to neutral will usually work at 5 to 10 kmh.

    It can be well-nigh impossible to select neutral from a standstill with the engine running. It's a snack as soon as you turn it off.

    Hard to imagine why that is, unless they did remove the selector mechanism to check it. Get used to it and don't worry - this is a standard, sequential motorcycle gearbox feature.

    All the best


    PS I really cannot imagine that I or NoShowAllGo would have withheld our answers because you have "not yet introduced yourself in the Welcome Lounge"!

    Feel free to ignore VCM and others who think this is a kindergarten where everyone must behave in a stereotypical fashion or be ignored....I'll quit before I say something rude. ;-)

    PPS Fresh oil doesn't really help you change gear on a stationary motorcycle, either.
  4. Don't stomp!

    Even though NoShow etc has been doing this for many years without damaging a selector fork or shift drum, it is a practise I would never recommend.

    Change gears firmly and fully once you are moving. Never force or stomp on the gear lever. It's simply not necessary, and shows a very poor understanding of the issues involved.

    He is possibly joking, but since you are/appear to be a n00b ;-) it is better to learn the right way from the beginning.

    All the best :)

    Trevor G
  5. On the contrary Trev -I have thought about it & my feeling is that a little bit more pressure on the shift drum/forks is preferable to listening to the poor little engine scream its lungs out as it over revs & the nasty graunching sounds emanating from the gearbox as the dogs chew away at the mating slots in the gears :grin: :grin:
    As I said, I think the problem may be solved by increasing the leverage ratio on the shift shaft, which incidently arrives at the same result as jumping on the gear lever a little bit harder :) I'll get around to it one day hehe
  6. too much force on the gear shifter will bend the shift forks
  7. I am in no way trying to start a shit fight here -but there is a site (can't find it at the moment) that offers a "shift kit" for the VFR 750 & 400. Basically it comprises of a stronger detent spring for the shift drum to force you to use more effort when selecting gears. No more missed shifts.

    I however am a lazy b@stard & do not wish to be forced to work harder to change gears. Explaing my reasoning for opting for a slightly longer shift lever to increase the leverage force :LOL: :LOL: :LOL: :LOL: I reckon you would have to jump on the lever pretty hard to bend a shift fork though. Only times I have seen or heard of it happening were due to crashes.
  8. I find it nigh impossible sometimes to find neutral with the bike off, but i've never had a problem at a standstill when its running :S