43 Mph Huffy Cranbrook!

Discussion in 'Photos & Bicycle Builds' started by LewiSStyle, Mar 30, 2015.

  1. LewiSStyle

    LewiSStyle New Member

    Hi Everyone!:D

    I build a 66cc grubee motorized huffy and I did a couple of upgrades now I get 43 mph.

    The handling is not bad but a those speed I would like to get more stability.:grin5:
    Any advices?

    I did the folowing mods:
    Head shaving
    correcting the transfer ports
    port matching
    jaguar torque pipe
    homemade boost botle
    32 tooth sprocket
    IMG_0342.jpg IMG_0404.jpg IMG_0406.jpg IMG_0408.jpg IMG_0410.jpg

  2. dougsr.874

    dougsr.874 Active Member

    Hope you have a helmet and are caught up on your prayers....its a bicycle not a motorcycle....Simply not meant for those speeds..
  3. LewiSStyle

    LewiSStyle New Member

    Yeah, I wear a full face helmet, a jacket and gloves, safety isn't an option when you ride fast :helmet:
  4. wheelbender6

    wheelbender6 Well-Known Member

    A heavier front wheel makes the motorbike less twitchy at speed. Try to find a front wheel from an industrial bike like a Worksman.
  5. LewiSStyle

    LewiSStyle New Member

    Thanks for the answer, I will try to find a heavier wheel in the town.
    Is a double wall rim heavier than a single wall?
  6. KCvale

    KCvale Motorized Bicycle Vendor

    I'd say you can call it fast enough for now.

    Now make it be able to stop just as fast!

    All I can see in the pictures to stop you is the stock $89 Huffy Cranbrook's coaster brake.

    Just for your information that back wheel is the most unreliable piece of junk to ever be put on a bicycle and a main reason the thing is under $100.
    Do want just THAT to be your ONLY way to stop at 40+?

    Absolutely NO motorized bike is safe to operate with only a coaster brake, period.

    It's all fun and exciting to go real fast, and you may be the best bike rider in the world riding where there is no traffic, but the day will come when something gets in front of you and you won't be able to stop in time.
    This never ends friendly for you bud, trust me on this.

    Throw a pair of C-brakes on it to a dual pull brake lever behind the throttle, ~$35, save the coaster brake for emergency stop before that Huffy hub gives out, and keep the pads fresh.
    As we say, 'its better than nothing', but if you want to mess with the front wheel look into maybe a new front fork with at least a V-brake mount or a drum brake front hub.

    Just my 2ยข on common sense safety.

    Or check your healthcare and gear up because right now you are really flirting with some really costly real bodily harm.
    Last edited by a moderator: Dec 18, 2015
  7. LewiSStyle

    LewiSStyle New Member

    Yeah I seriously think the the thing is fast enough!
    I'm putting front disc brakes on the bicycle.

    what is unreliable with te rear wheel? the rim? Spokes? Hub? Bearing?

    In canada the cranbrook is around 150$ :(
  8. KCvale

    KCvale Motorized Bicycle Vendor

    Since you will be replacing the fork and wheel to go discs might as well get a shock front fork with brake bosses.
    Maybe just a fork with disc and V brake bosses and a set of V-brakes first.
    That way you don't have to spring $200+ more to go disc for now but have good front brakes.

    Everything inside the hub is iffy at best, otherwise a good wheel and you can upgrade the coaster brake inside.
    The thing is, most don't and I seen what was left after a motorized fail on a few.

    I'd just keep a close eye on it.
    Hold your frame with one hand and see if you can push the wheel back and forth.
    The hub shouldn't move on the axle.

    Don't rely on that coaster brake, put a C-brake in back too bud ;-}
  9. wheelbender6

    wheelbender6 Well-Known Member

    "Is a double wall rim heavier than a single wall? "
    A steel rim will be heavier. I think most double wall rims are alloy/aluminum.
  10. LewiSStyle

    LewiSStyle New Member

    Hi everyone!

    I just finished putting a disc brake on it.
    Now the thing have braking power! :D
    I used a pocket bike disc brake, I machined the fitting myself so it end up a 0$ :eek:

    Since I removed the wheel to instal the disc brake I also trued up the wheel and put a good quality tube. Now the handling is sooo much better

    I checked the rear wheel and it didnt have any play so it is good for now, i'll check it after every ride

    IMG_0427.jpg IMG_0428.jpg IMG_0429.jpg IMG_0430.jpg IMG_0432.jpg IMG_0437.jpg
    Last edited: Apr 4, 2015
  11. KCvale

    KCvale Motorized Bicycle Vendor

    Very Cool man, good job mounting a disc to a regular wheel!

    How did you mount the caliper?
  12. LewiSStyle

    LewiSStyle New Member

    Thanks, I'm very happy of the result.

    I mounted on the stock fork with 1/4 bolts and a homemade steel bracket

    IMG_0469.jpg IMG_0470.jpg
  13. LewiSStyle

    LewiSStyle New Member

    Hi everyone!

    My motorized bicycle is now a joy to ride with the disc brake but I am still searching to obtain more stability.

    I did uprade the thins tubes with some heavy thornproof tubes to incrase the weight of the wheels, it helped but the handling is twichy like any bicycle...

    I would like to have motorcycle like handling, a smooth steering. Is this possible?

    Thanks :)
  14. Slogger

    Slogger Member

    Changing the geometry of the front end would fix it but it isn't easy or cheap. Some of the springer forks space the wheel farther forward, and there are those odd suspension mods using pivoting arms at the bottom of the fork with springs anchored on the front of the legs. If you go this way though, your brake setup would have to be re-done. Raking the gooseneck would mean welding or tigging (aluminum?) but the brakes you've built would work.
    A steering damper might be easier and fix the jitters for ya.
    That's a nice bike you're building, the brakes are really nice.
  15. LewiSStyle

    LewiSStyle New Member

    So if I understood correctly, a fork that put the wheel father foward will make the handling smoother?

    then why a motorcycle fork isn't curved foward like a bicycle one?

    Thanks, I did spend a lot of time on it :)
  16. Slogger

    Slogger Member

    It would make the steering slower. The longer wheelbase will make it a little more stable at speed, also. This is only if it is a good quality fork without any wobbliness.

    Motorcycles use the rake of the gooseneck to set the geometry along with other minor tricks like having the axle bosses on the front side of the fork sliders rather than centered on them. A curved fork wouldn't allow the typical suspension on a motorcycle work.
  17. LewiSStyle

    LewiSStyle New Member

    I did a little search about bicycle and motorcycle forks and it seems that increasing the curve (offset) of the fork will reduce the trail length and it will make the handlebars twichier (not good)

    So a strait fork will in theory increase the trail lenght and it will make the handlebars harder to turn.

    Do this make sence?
  18. Slogger

    Slogger Member

    I'm unable to explain it any differently than I did up above. Lengthen the wheelbase = more stability.
    Kick the front wheel out in front of the fork, you'll have heavier, slower steering.
    I wouldn't re-bend any fork tubes on my bike. I'm too old and heavy to risk it.
  19. LewiSStyle

    LewiSStyle New Member

    I understand your explaination about the lenghtening of the wheelbase.
    However from what I learn, if you do it by increasing the curve of the fork it will mess the trail length, I think that we need to do some experimentation on that... Bicycle_fork_geometry-en.svg.jpg

    Take a look a that, it explains the effects of the trail length: http://bikearama.com/theory/motorcycle-rake-trail-explained/
  20. RumblingV8

    RumblingV8 Member

    I'd say a fork with suspension might help. On my 2nd build (also a cranbrook) I'm still in break in but having ridden at moderate speeds going from stock fork to springer fork (which also gave slightly longer wheelbase) is more stable. Makes me wish i went that direction with my first bike. I believe depending on the fork you can get them with disc brake brackets either built in or an adapter, which in your case you can competently make yourself so you could easily keep your front brake setup. Or if you go with a regular mountain bike suspension fork, it makes disc brakes easy too. Depends on the look you want, i guess. I enjoy the simplicity of the springer.