Engine bogs down releasing clutch in 1st gear


Tagged: ,

Viewing 15 posts - 1 through 15 (of 24 total)
  • Author
    Posts
  • #31763
    AvatarMako
    Participant

    Hi everyone, I’ve recently purchased a new vitpilen 701 (my 19) and I was experiencing an annoying behavior when releasing the clutch, basically when I try to start moving from a stand still in 1st while releasing the clutch the engine bogs down (hopping a bit) right before the first gear is fully engaged ( ≈10km/h), and to prevent the bike from stalling I have to drag the clutch more than I desire especially if I want to start moving a bit more quickly.

    So I was wondering if this “hop” is normal for the 701 or not if I need to check something out.

    Thank you:)

    #31765
    VanessaVanessa
    Participant

    I’d start by checking the clutch switch and making sure it operates as soon as the clutch lever is pulled.

    #31767
    AvatarMako
    Participant

    Thank you for your quick answer ! but I don’t think is related to the clutch switch because this vibration happens right before releasing completely the clutch and always at the same rpm/speed in 1st and other than that the clutch works fine (for now) so I was wondering if it is a characteristic behavior of the bike.

    But with your answer I assume that you are not experiencing any particular vibration before fully engaging 1st gear right?

    #31768
    VanessaVanessa
    Participant

    Well, I don’t have a 701, my bike is the 401, and also it’s fitted with a Rekluse centrifugal clutch so I don’t use the clutch lever when pulling away in 1st gear. I was just thinking of things you could check, just trying to help. And no, my bike has no bad vibrations or bogging down when I pull away. My Harley on the other hand has loads of not very nice vibes right when I pull away from rest, I have to slip the clutch like mad on that bike to get a smooth pull away.

    #31770
    AvatarMako
    Participant

    <p style=”text-align: left;”>Thank you anyway for your suggestion! I hope is something that someone else experienced and solved…city riding with this behavior is annoying</p>

    #31771
    Satur9Satur9
    Participant

    Try this test. Bike off in neutral. Pull the clutch lever. A bunch of times. Then start the bike let it warm up good. Then repeat the process. If your noticing a difference in feel during either test. Then clutch slave is sticking and will fail soon. Even if it isn’t the slave it isn’t normal behavior . So get it to dealer.

    • This reply was modified 11 months ago by Satur9Satur9.
    #31773
    AvatarEnginseer
    Participant

    Honestly, to me that just sounds like you are giving it too few revs for the speed you release the clutch.
    Either try to release the clutch slower (you say it does not happen then) – or if you want to get going a little faster rev up higher.
    The motor is a single cylinder and has quite a lot of torque. That is why instead of staling you get that hopping, it still has enough power to move you.
    The Vitpilen likes around 2500 to 3000 revs to get going.
    I am still in second gear where my mate with his CBR 600 is already chugging along in fifth. Differences of motor setups and cylinder count.

    For reference: I do get that hopping in 2nd if I am lower than 20km/h, in 3rd below 35km/h and in 4th if I am below 55km/h. 6th gear needs almost 100km/h to be smooth.

    Hope that helps,
    Ramon

    #31774
    AvatarJeff
    Participant

    Enginseer has exactly the answer In My Humble Opinion.  His experience is my experience exactly. Keep the revs up and take off smoothely! The 701 single hops at less than 3000 rpm.

    #31776
    BferrisscBferrissc
    Participant

    The 701 is geared high – drop the front sprocket to a 15T  and you’ll find much better tractability at low RPMs…

    #31780
    AvatarMako
    Participant

    Satur9 I’ll try your test and report what happens

    #31781
    AvatarMako
    Participant

    Enginseer to be honest I’m not a great fan of riding clutches so what you are saying might be truth, but to specify the problem is not the hopping feel that bothers me but the fact that if I don’t adapt to it with the clutch(for example not releasing it linearly but keep it a bit more pressed when this hop happens) the bike will stall at ≈10 kmh

    So maybe it’s me but if any of you want to try, start moving the bike with only the clutch and no gas and tell me if you feel the aforementioned hoopping before fully engaging 1st

    #31784
    David BrazilDavid Brazil
    Participant

    It is this: “The 701 is geared high – drop the front sprocket to a 15T and you’ll find much better tractability at low RPMs…”

    The bike is geared very poorly. I noticed it on my first ride and very much disliked it. There is a thread or two on this forum about changing your gearing, and it works wonders.

    I initially went to a 44 rear, but it wasn’t enough, then went to a 15 front, and that felt perfect down low, but I feel I need a 7th gear, so I think I’m going to go back to a 42 rear and keep the 15 front, and it will be a good compromise.

    Try it. You’ll like the difference. It is VERY noticeable in town. If you tour or drive at high-speed much, it’s probably not for you, as you’ll desire a 7th gear.

    Cheers.

    #31785
    AvatarMako
    Participant

    Yes I agree the bike definitely needs different gearing and maybe a decat and a map to improve <3000 rpm vibrations, the only thing that stops me is warranty

    thank you for all the answers!

    #31786
    AvatarEnginseer
    Participant

    It definitely works but it takes a lot of effort and lots of patience to get going with only the clutch in first.

    I don’t know about gearing, I am quite happy with it but I more than once heard that remapping to make it run a bit richer in the low revs makes it way smoother.

    #31854
    DuctTapeDuctTape
    Participant

    Hey Mako, I also didn’t like the low-rev behavior (same thing you’re experiencing), it’s poor fueling from factory. Buy a fueling dongle. I’ve got this one from Rottweiler, best $29 you’ll spend on this bike: http://www.rottweilerperformance.com/rottweiler-fueling-dongle/ . This will solve the stalling at low revs.

     

    PS: I also recommend changing the sprockets if you can! I’m using 15-42

Viewing 15 posts - 1 through 15 (of 24 total)
  • You must be logged in to reply to this topic.