Simple chain drive setup...

Discussion in 'Rack Mounted Engines' started by s_beaudry, Sep 2, 2008.

  1. s_beaudry

    s_beaudry Member

    Ok, I have this idea for a rack mount setup, looking for your thoughts as to whether it will work or not...

    I will be using this engine, so keep this in mind....

    The engine has a 5/8" driveshaft on it which is very nice! I want to use a standard 5/8" bore centrifugal clutch commonly used for gokarts and such with a 10 tooth #41 chain sprocket on it as pictures here...

    I would run the chain down to a standard 44 or 48 tooth sprocket (standard HT kit sprocket) on the back rim.

    Of course I will have to work in a tensioner somewhere for the chain, but should not be too difficult.

    I have read a few threads on here that say you can run a #41 chain on them.

    My questions are...

    Would this setup work on a bicycle?

    Is a gear ratio of 4.4 to 1 good for power?

    Just to be sure, this is a standard CCW engine, correct?

  2. ocscully

    ocscully Member

    Not enough reduction

    The set up you describe is not near enough reduction. You need to get in the neighbor hood of 18.75:1 total reduction to have a viable motord bike with the Honda motor. Also The clutch you are thinking about may give you problems with the Honda motor. Its made for motors that idle at alot lower rpm than the Hondas 2000 rpm idle and the motors its designed for only rev to 3600 rpm rather than the Hondas 7200 rpm range. The Honda is CCW rotation.

    Last edited: Sep 2, 2008
  3. conradcliff

    conradcliff Member

    I'm actually looking to utilize the GXH50QHA myself. Where can I get the proper clutch for this?

    Thanks for any help! :grin:
  4. 5-7HEAVEN

    5-7HEAVEN Guest

    Honda GXH50 Adaptor QXA 1.5 inch thick

    Aditional Image(s):

    Adaptor CNC machined for the Honda GXH50 QXA type engine. This has four drilled and tapped holes 6 mm x 1.0 and four counter drilled holes for the 1/4-28 FINE thread x 1-1/2 inch long socket head cap screws. This is a custom machined part so the Honda GXH50 can be used with the Staton-Inc drive systems like our 18.75 to 1 gear boxes, friction drive kits, double bearing clutch housings and some other brands of equipment.
    This adaptor can now be used without cutting the shaft of the engine to use with the Staton brand gear boxes and our friction drive kits.
    Price: $55.00
    Color Gray

    Send To Friend

    The products below were also bought by people who bought Honda GXH50 Adaptor QXA 1.5 inch thick
    Honda GXH50 Clutch Rotor Super Duty 3 shoe
    Honda GXH50 49.3 cc 2.10 hp 15.8 mm - 5/8
    3/16" x 1/2" round key
    6 MM x 18MM Fender Washer, Zinc
    1/4-28 x 1-1/4 FINE thread, Socket Head Cap Screw.

    Related Products. The products below are related to Honda GXH50 Adaptor QXA 1.5 inch thick
    1 DBCA 15 mm Double bearing clutch Assembly
    1/4-28 x 1/2 FINE THREAD Button Head
    1/4-28 x 1-1/2 FINE thread, Socket Head Cap Screw.
    6 MM x 18MM Fender Washer, Zinc
    Double Bearing Clutch housing Assembly 1/2 inch OD Shaft
    GC Gear & Chain Drive kit - NO ENGINE
    Gear Box 3.11 to 1 reduction small compact gear box
    Honda GXH50 49.3 cc 2.10 hp 15.8 mm - 5/8
    Honda GXH50 Clutch Rotor 76 mm OD, 15.8 mm - .62204 / 5/8
    Honda GXH50 Clutch Rotor Super Duty 3 shoe
  5. conradcliff

    conradcliff Member

    Thanks for the reply! Hopefully I haven't overlooked something but I don't plan on using the gear reduction box, I only need the clutch with a housing around it that has a sprocket on that for a chain. (not sure what the housing would be called, if you would like to enlighten me so that I wont sound like a moron next time I would appreciate it). Basically I just need a typical go cart centrifugal clutch that can handle 7000 RPMs and engages just above this engine idle speed; which I think I read somewhere is 2000 RPMs. I intend to create my own gear reduction system.

    Thanks for any help!
  6. 5-7HEAVEN

    5-7HEAVEN Guest

    search the go kart sites for clutches.
    Last edited by a moderator: Nov 2, 2008
  7. ocscully

    ocscully Member

    The clutch linked to above includes the clutch bell that has the chain driver attached. The housing talked about in other posts in this thread is an adapter that allows the Honda GXH50 to be mounted to various reduction gear boxes that are readily available for the smaller weed-wacker type of motors. So for the type of drive train I believe you are thinking about you do not need this housing. One fearture you may want to consider in a clutch would be that the clutch can be mounted with the driver either inboard or outboard. Having the clutch mounted to the motor with the driver inboard allows you to keep the motor mounted closer to the centerline of the bike. This is a big plus in my opinion. Also you want to be sure that the clutch comes with the shaft extender bushing for mounting onto the short shaft of the Honda motor.

  8. conradcliff

    conradcliff Member

    Ah! Clutch bell..I'm sure to sound much more intelligent now. Thanks a ton for the help, I'm going to search around and see if I can get it any cheaper. Are there any specific numbers I need to look for in order to find out if it will work with a typical bike chain?
  9. conradcliff

    conradcliff Member

    Ok, so I found that bike chain is #40. Now I'm looking for the shaft extender bushing. Do you know how long of one I will need or is that going to depend solely upon which centrifugal clutch I choose. Also should I be looking for a clutch that is smaller than 4"OD?

    Thanks again for all your help!
  10. kerf

    kerf Guest

    Am I missing something, a 10 tooth drive sprocket to a 44 tooth driven sprocket on a 26" wheel, ain't gonna work. I know I've got something wrong, what is it?
  11. ocscully

    ocscully Member

    The length of the bushing varies depending upon the width of the clutch. I bought the clutch for my project that uses the Honda GXH50 without a gear box from They offer a special clutch that has been optimized for use on the Honda motor and will ask you what length shaft your motor has as there are at least 2 different lengths. (1&1/4 and 1&5/8) The clutch I bought from them was the one they offer with a 5mm Metric Timming Belt Driver and happens to be quite wide but the clutch with a #41 Chain driver is probably quite a bit narrower. The cost of the clutch from Max Torque was more than other outlets but came with every thing needed to just mount it right up to the Honda motor. Send them an e-mail or call them you will probably be dealing with a man named Jim Donavan he owns the company and he has alot of knowledge and is more than happy to share and help out.

    Why is the OD of the clutch important if you are not using one of the gearboxes?

  12. 5-7HEAVEN

    5-7HEAVEN Guest

    Sir, you need more gearing near 18.75:1 for this 7,000 rpm engine, as mentioned by others. A 10-tooth drive sprocket and a 188-tooth rear sprocket will do the job....

    or use the entire Titan drivetrain to facilitate the install.:grin:
  13. 5-7HEAVEN

    5-7HEAVEN Guest

    Conrad, you should start your own post. I'm confusing you with the OP.
  14. conradcliff

    conradcliff Member

    I'm going to be making my own gear reduction jackshaft (possibly shiftable) which will be running to a front freewheel crank similar to SBP's system. I don't have the numbers figured out yet, I'm just trying to figure out where I'm going to get the parts.

    Oscully: I wasn't too sure if I was going to be losing too much energy be adding on the addition rotational weight of an over sized clutch. I didn't know if people were using smaller ones or not. Thanks a ton for the info and the link I will definitely check them out!

    Sorry about taking over this post, I didn't want to make anyone upset by bringing up an old subject in a new post. I'll start another thread with all the info I've gathered.

    Thanks for all the help everyone!
    Last edited: Nov 2, 2008
  15. ZnsaneRyder

    ZnsaneRyder Member

    The Hilliard Clutch will work. It's a 2300 RPM clutch which may be enough for the idle. If not, you can get upgraded 3000RPM springs.

    The Hilliard clutch is a BRUTE. It's rated for 13HP! With only over 2HP from the Honda, the clutch should last much longer. I have that same clutch (but 3/4) on my 6.5HP 196cc engine, and as long as I treat it good and lube or replace the bushing as needed, the clutch lasts.

    I just got that same clutch for my 80cc rack-mount project. The engine uses the same 5/8 shaft like the Honda.

    Also, if the engine is too wide, you can use a jackshaft to get a double-reduction and also properly align the power to the wheel.

    Also, get an extra bronze bushing to extend the clutch life.
  16. NoPed

    NoPed Member

    I know this is an old thread; hope someone can reply. I just bought one of these honda gxh50's and did not realize it had a longer shaft length which seems to be incompatible with all the various kits. on the staton site today they offer the adapter, three shoe clutch and nearly everything else i should need; the price is 129 dollars. i did not anticipate this extra cost or i might have opted for the smaller engines that mate up with everyone. is there another way round this? is having a machine shop shorten the shaft counter productive or just as expensive? some other adaptation?
    For all you who have been helping me along with my first build, let me say that i'm going with a friction drive (this is where i found out about the adapter). I intended to have two bikes anyway so i can still ride if i broke down; with the friction, i can put it on the bike i have now and roll. I will save up and buy something nicer later on. Maybe the gearboxes will be perfected so buying one will be a no brainer. I did just notice that staton sells their gearbox separately; i have not heard on the forums of anyone utilizing it with their build. So it's friction for now and if i have to have the clutch adapter, fine, i'll just accept it and move on.

    thanks again guys
  17. cycledude

    cycledude Member

    If the clutch doesn't work to the engine rpm you can always adjust the rpms or add more springs to the clutch, there is a **** of a difference between 37 bucks and hundreds.
    the ratio for the sprokets can be overcome by adding a shaft somewhere, Im still trying to figure out where.
  18. cycledude

    cycledude Member

    ZnsaneRyder, the hilliard clutch will NOT work , the shaft is almost 1" short when the rotor and housing are mounted on the engine.
  19. cycledude

    cycledude Member

    Maybe I should mention that the hilliard clutch is no good for the honda 50cc, that's better.
  20. damdav1

    damdav1 New Member

    im running a 10 tooth clutch to a 60 tooth rear sprocket it powers along at 35 mph i had tried to runn a 10 to 44 but the bike had to be running and rolling to get it to go it wouldnt start from stand still motor just died