wc polini rep 46cc mtb 8 speed help

Discussion in 'Performance Mods' started by bhaydonsuperpocket, May 5, 2012.

  1. bhaydonsuperpocket

    bhaydonsuperpocket New Member

    ive got bike running with internal hubs sg8r20 the problem is that the hub is very close ratio and when u rev out and change next gear the revs only drop 1000 to 1500 rpm so it revs fast and all u do is change and didnt do much in each gear when i ride i start in 1st rev out then fourth gear rev out then 8 top but i think needs more top end as in smaller rear sprocket and a hub with wider ratio between gears dont get me wrong it goes very good and revs hard and fast and top speed probley 45 to 50 kph ill post up gear sizes and ratios to morrow any 1 no ove a hub more suited 4 me tar:evilgrin:

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  2. 5-7HEAVEN

    5-7HEAVEN Member

    What top speed do you want, and where in the rpm range is your top hp and torque? When you know that, then you can build your gear ratios. If the rpms don't drop enough during shifting, you can skip gears. With my Tanaka 47R and shift kit, my first gear is about 46.36:1. Then I usually shift to third, then fifth, then seventh. On steep hills, then I'll use every gear, so the rpms don't drop.

    You need to make sentences with punctuation marks(periods). It's not easy to read your message.
  3. HeadSmess

    HeadSmess Well-Known Member


    my 650 only drops 1500 or so on each gear change once im over 5grand....

    bit of a dog taking off in 4th though... i know, ive tried...:eek:

    gear it so first will at least get you going, and then live with it :)
  4. jaguar

    jaguar Well-Known Member

    Just gear it up then. You may never then use the top gear but you will have more rpm drop each time you shift up.