Prepping a bicycle before installing an engine.

Discussion in 'Electrical' started by oliverw123, Sep 8, 2016.

  1. oliverw123

    oliverw123 New Member

    This information is for a typical mountain bike. After riding for a few months I realised that certain components can be removed from the bicycle yet still maintain good functionality. The purpose of this is to simplify and thus make the bicycle less prone to failure and easier to maintain.

    First thing I do is get rid of all gear cabling. You don't need to change gears with the engine installed but you still want to have the ability to pedal if say, you run out of petrol. Disconnect cable (and remove) front derailleur and disconnect cable on rear derailleur. You can go as far to remove the front upper chain rings but leave the bottom smaller one, looks neater and saves a little weight. Now your chain will by default sit on the smaller chain ring on the rear cassette. This makes it too hard to get going with all that weight so all you need to do is adjust the screw on the derailleur that shifts the chain up the chain ring as far as it will go to enable easier pedaling. It should sit somewhere in the middle. Remove the shifter components from the handlebar. Now you have more space to install the throttle and clutch lever.

    The bike will be quite a bit heavier with the engine and other components so it is a good idea to grease wheel bearings liberally and also the pedal crank bearings, using good grease. Use good brake pads front and rear too.

    If you don't have front shocks, balloon tyres will make the ride a lot softer, this I would recommend anyway regardless of front shock.

    I forgot to add, get rid of the kill switch. Use the choke or release the clutch to kill the engine. After 5 years running, my clutch ppads were hardly worn.
    Last edited: Sep 13, 2016

  2. Steve Best

    Steve Best Active Member

    Hmmm, I use the pedals and gears all the time, mainly so Johnny Law doesn't stop me for riding an unlicensed scooter, but also for exercise and speed when I want it. You are right, the handlebars do get cluttered. 2 shifters plus one for choke and I use another for a thumb throttle.

    I've burnt out 2 rear wheel bearings (different wheels) in a couple thousand miles. Good advice on the grease.

    BRAKES! Oh yes! Last year I didn't know much about bike brakes, but if you wanna stop, ya gotta learn.
    Linear-pull brakes, AKA direct-pull brakes, AKA Shimano's trademark V-brakes are the way to go in rim brakes.

    Also not bad are dual pivot center pull brakes. The dual pivots near the braking surface are key to success:

    If you plan on any significant speed (over 20mph) avoid at all costs single pivot brakes. TOO MUCH flex to stop well.

    Also avoid chromed rims, slippery as eel slime when wet. Aluminum rims seem a bit better but I notice mine wearing significantly.

    Look up bicycle brakes on Wikipedia and get schooled. Stopping is more important than going.

    Going over every nut and bolt to make sure it is right is good advice. Read some books on bike care is important.

    HOLY SPOKES! Loose spokes are a big problem. Learn how to tighten them just right and how to true the wheel and sprocket.


    A piece of wire might do, but nice to have some fancy rocket science tools in your box.
    Dial indicator and magnetic base for less than $50 at Harbor Freight or Princess Auto.
  3. skyash

    skyash Active Member

    Also if you get a mb from kmart for $80 everything will wear out in 2 months you get what you pay for . $2 brakes pads are good and cheap but $5 brakes pads will be better and so on and on something like brakes it can save your life to pay more .
    zippinaround likes this.
  4. FurryOnTheInside

    FurryOnTheInside Active Member

    You might like Ryde CSS (carbide supersonic coated) rims, supposed to last 4 times longer and the "top choice [of rim brake rims] among RTW cyclists". The Andra 40 is 25mm internal width too, so stiff as anything. :)
  5. JunkyardDog

    JunkyardDog Active Member

    I have done 2 mountain bikes that way. Remove the front derailleur and all but the smallest front sprocket. Remove both shifters and both cables. Put the chain on the largest rear sprocket, and adjust the rear derailleur so it stays put. At this point it is nothing more than a chain tensioner, and you are in the lowest gear the bike has. If motorized bikes are legal in your area, you don't need to pretend to pedal, but you will need to pedal every time you take off from a stop. Being in the lowest gear ratio will help considerably there. As for exercise, I'm past the point where I can pedal a bike more than a few revolutions of the crank, so that part doesn't matter. That's why I have a motor.
  6. oliverw123

    oliverw123 New Member

    This is my bike. The engine has been running for 5 years and has probably 20 000km on it. The odometer I had stopped at 999 and that was 4 years ago. The engine used to be on another bicycle which was driven over, don't ask. It was a similar bike which I stripped completely and had the frame epoxy coated glossy black. I also had a fuel tank mounted behind the seat which I will do to this one too.

    Attached Files:

  7. Yeshua

    Yeshua New Member

    So you don't need the rear gear shifter for the bike? Reason I ask is cuz the shifter is physically part of the break lever and I want to install a double brake. By removing my break lever I lose control of the gears. Do I need them?
  8. zippinaround

    zippinaround Active Member

    My advice for prepping the bike ,
    1) remove wheels open up the bearings pump full of grease , or install a grease nipple on the axel if possible then put back on.
    2) check the bottom bracket bearing same procedure.
    3)if a cheap bike replace the brake pads at very least , else fit a disc brake one from minimoto/pocketbike will do.
    4) make sure every nut and bolt is tight/secure.
    Done just 4 steps , removing the derailed will make no weight difference gain nothing and lose all your gears why?
  9. Yeshua

    Yeshua New Member

    I would be removing the thumb 7 speed gear shifter. Do I need to be able to shift bicycle gears with kit. Can I do without the ability to shift gears on a 7 speed bike(right hand side rear wheel)
  10. zippinaround

    zippinaround Active Member

    I'd say leave unless you have no hills anywhere near where you'll be going/could break down, you can loosen the thumb shifter and move it over or turn it upside down?
  11. Yeshua

    Yeshua New Member

    It's all flat around here. So I should still be able to pedle start the engine tho?
  12. zippinaround

    zippinaround Active Member

    Once you can pedal it yeah it will start to
  13. JunkyardDog

    JunkyardDog Active Member

    If you intend to ride it only as a motorized bike like I do, you only need one gear. But it needs to be as low as possible, to assist in taking off from a stop. Most single speed bikes are geared way too high. You can remove the shifter cable without actually removing the shifter. Put the chain on the smallest front sprocket and largest rear sprocket, toss the front derailleur and lock the rear one in place with the adjustment screws. Much less to go wrong. If you plan on actually pedaling it more than what is required to get it moving, I'd use a friction drive setup. With an in frame motor, you are turning the motor chain, tensioner, and part of the clutch while pedaling. With friction drive you just lift the motor and drive unit off the rear wheel, and eliminate all drag.
    oliverw123 likes this.
  14. skyash

    skyash Active Member

    I don't think it a good idea to take gears off if you got them I would not want to pedal without them sometimes you are happy with the gear it's in till you try another one then you stick with it for a while or go back at least it's just a turn on the changer not getting off and playing with the derailer .if there's not much room on the handlebars get some straight ones ?
  15. Oliver

    Oliver Guest

    Weight is not an issue and why do you need to change gears?? You will still have one gear to use if say you run out of petrol.. that gear is one that you set the derailleur to whichever you choose. Removing shifters and cables neatens up the bike which equals less hassle and less clutter and lower maintenance.
  16. oliverw123

    oliverw123 New Member

    It is not a problem to leave the gears as they are. The area I ride in tend to be flattish therefore I just set my rear derailleur so that I have a balance between starting off and pedalling speed. I just like to simplify things and my suggestions are only that, suggestions.
  17. zippinaround

    zippinaround Active Member

    Sure if you live in a flat area it's fine I've only ever lived in extremely hilly areas so removing the gears seems like madness , many times I have had to cycle back home after something went wrong so no gears is a no go for me .
    FurryOnTheInside likes this.
  18. oliverw123

    oliverw123 New Member

    I never mentioned having no gears at all. If you read and understand my initial post then you'll get what I'm on about.
  19. zippinaround

    zippinaround Active Member

    Sure you did you said remove derailers and gear cabling which = no gears . Your left with a fixed gear unless you adjust the arm to a different screw which you can't do while moving,
  20. FurryOnTheInside

    FurryOnTheInside Active Member

    I'm with zippinaround. I see no advantage in removing the (working) gear system that can get you home if you have engine trouble. Single speed can be pretty annoying on flat ground too, due to the wind.
    Plus if you can't maintain a geared bicycle how do you expect to maintain a motorised bicycle.
    You can always remove the gears later on or limit the derailleur to one sprocket IF you have any problems later. Or just maintain your bike's gears.