Motorcycle carb for Honda GX100

Velodrome

Velodrome

Well-Known Member
Well My "MONSTER" GX100cc Honda arrived today :) I've only seen these things ever on dirt tampers and the throttle setup apperes totally unusable for a motored bike. More like a set and forget affair. Think mechanical cruise control. I just got the thing out of the box and havnt done any proper measuring yet; but some small engine expert on here might just have an opinion of the carb I should use. I dont intend to raise the RPM limit or overstress the motor but a custom; free flowing exhaust is in its future. I was thinking something like "THIS" : eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices Discuss...
 
the inside bore of the carb seems to be 15mm mounting holes seem to be ~42 mm but are at an odd angle guessing about 10-15 deg rotated clockwise. intake side is 19mm. and intake port about 19mm square. I've searched this forum, and I know I went out on a limb here, as I THINK I'm the first to use this particular motor...
 

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Well I am in the same boat with my GC160. By the time I figure out a set-up for the throttle I might as well opt-out and purchase the Mikuni setup from AGK and be done with it....you might want to do the same.

affordablegokarts: Carburetor Adaptor With Pulse Fitting, 22mm Mikuni & Air Filter

On a different note: I am running a HF6.5 upright on the Dyno four stroke with a stock rod and pull it up to 6000RPM with no issues. This is my low budget 6.5 that runs hard. So that 99cc should be fine.
 
Thanks guys. CCC: Id love to do just that but Im thinking a 22mm carb is gonna be WAY too big for a little 99cc The stock carb is 15mm and made for the RPM range the motor is designed for, I might be safe with something like this. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290505448477&category=35597&_trksid=p5197.c0.m619 its for motrorcycles and pitbikes and such,; only 1mm larger bore. I have no idea what RPM range the motors ran at, that used this carb, but I see them advertized for everything from 50-110cc. HUMMMM...Wonder if the AGK adapter would bolt to this carb then to the ODD asymetrical bolt pattern on my motor?
 
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Well After fiddeling about for the day with the GX100 I decided I'd never trust it being used as a bike carb. Its fine for garden equipment that dos'nt go 20-30 mph. SO. I just pulled the trigger on this. eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices I'll beat on it till it works. CCC. Do you know if the AGK adapters are an asymetrical bolt pattern like mine or are the the regular MC style??? Too late to call em tonight
 
VeloDrome-

I am really stoked to see that you are building up a project with this engine!

I have been looking at these engines for a while now, wondering why they weren't motoring bikes everywhere...

Where is the best place to get this engine (I think $350 + shipping is about the cheapest I've seen..), and if you get a chance at some point, could you measure how tall the engine is without the tank on top? I'm hoping I can somehow shoehorn it into a Felt Chief frame.....
 
Velodrome said:
the inside bore of the carb seems to be 15mm mounting holes seem to be ~42 mm but are at an odd angle guessing about 10-15 deg rotated clockwise. intake side is 19mm. and intake port about 19mm square. I've searched this forum, and I know I went out on a limb here, as I THINK I'm the first to use this particular motor...
Click to expand...

Now i have to go look, i have one of these engines it came off a lawn edger but the carb looks a lot like a Honda110 three wheler carb. I got it at a garage sale because the guy was haveing trouble with the carb. I don't remember it haveing a angle mount,i will look later today.
Running a bigger carb will not hurt anything as long as its not to big and you funnel down the to match the port. If it runs to rich you just lean down the mixture screws or setings.
I am excited to see what you do with it .............Curt
 
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