97cc of Flathead Fury! I'm now riding a rolling space heater!

[miked826]

Top Speed: 34 MPH @ 3400 RPM (governor removed) on a 50 tooth sprocket.

Idles at 950 RPM to no ill affect.

My bike is now a thumping, grip shaking, rolling space heater. Man this thing puts out some heat. LOL

What did I have to modify to swap out a already mounted HS49 for this thing? The crankshaft was shortened and diameter reduced to 5/8". Mounting plate for the engine and the EZM QMatic were both butchered with a Dremel Tool to line up the holes with 97cc Lifan. Exhaust flange holes were redrilled. Carb was swapped out.

Was it worth it? I'd have to now say yes, after riding it a while.

 

[miked826]

 

[Intrepid Wheelwoman]

Yay! - another flathead bike

I very much like the look and style of your bike Mike.


(St. Villiers pray for me and keep mine eyes from temptation......)

 

[miked826]

Thanks much. I just need to reduce my rear sprocket size now to get my speed up. It's all torque right now.

 

[dodge dude94]

Looks badass. What engine/frame are you running?

 

[miked826]

Looks badass. What engine/frame are you running?

Thanks.

The engine is the "50 State Emissions Legal" Doodlebug DB30R 2.8 HP from OMB Warehouse.

The bike is a 2012 Felt MP.

 

[dodge dude94]

Thanks.

The engine is the "50 State Legal" Doodlebug DB30R 2.8 HP from OMB Warehouse.

The bike is a 2012 Felt MP.

Nice. And it's a 97cc? Sure looks small...lol

Did you put the forks on it? What forks?

 

[miked826]

This 97cc engine fits in the exact same size hole in your bike frame that a Huasheng 49cc fits. It is much wider than the HS49 but it's also cheaper or the same price as the HS49. Had I known about these facts before buying the Huasheng, I never would have bought the Huasheng. It just doesn't make an ounce of sense if you compare the two motors, spec for spec, pound for pound and dollar for dollar. Plus the 97cc just sounds hellacious compared to the 49cc. With a free flow exhaust it sounds like a real motorcycle idling. I swear if you stand close enough to it you can feel the ground shaking. LOL

 

[dodge dude94]

THAT. IS. AWESOME.

That's why I thought it looked more like an HS49. You said your current top speed is 34 mph, how quickly does it get you there?

 

[miked826]

THAT. IS. AWESOME.

That's why I thought it looked more like an HS49. You said your current top speed is 34 mph, how quickly does it get you there?

LOL Pretty dang quick as you can imagine but that is also with electric hub assist (2250 Watts) on the rear wheel. It get's to 34 MPH in nothing flat and climbs up any hill with ease.

It feels like I'm driving a car in 2nd gear but can't shift any higher.

The redline on that engine is 5200 RPM with the governor removed. How long it will last at 5200 RPM is unknown to me at this time.

 

[dodge dude94]

LOL Pretty dang quick as you can imagine but that is also with electric hub assist (2250 Watts) on the rear wheel. It get's to 34 MPH in nothing flat and climbs up any hill with ease.

It feels like I'm driving a car in 2nd gear but can't shift any higher.

The redline on that engine is 5200 RPM with the governor removed. How long it will last at 5200 RPM is unknown to me at this time.

What size sprocket are you thinking of gearing it down to?

 

[miked826]

What size sprocket are you thinking of gearing it down to?

Somewhere between 40 and 44. I have to be careful though cause I'm surrounded by steep hills, so I can't get too Speed Drunk, even though I'd love to. LOL

The big difference between the 97cc and 49cc is that the 97cc keeps pulling and pulling, where the 49cc just flat gives up and starts slowing down.

 

[Harold_B]

Nice, clean build Mike. I have the same 97cc on my Felt with sprocket ratios of (10/30) x (10/44) = 13.2. It cruises fine at around 30mph and will haul my 195lbs plus the bikes ~125lbs up some decent hills though I wouldn't say it isn't without a lot of effort. Take off is a bit sluggish. I like the electric booster hub you have going there and vaguely recall the build thread. Have a link by any chance?

 

[miked826]

Nice, clean build Mike. I have the same 97cc on my Felt with sprocket ratios of (10/30) x (10/44) = 13.2. It cruises fine at around 30mph and will haul my 195lbs plus the bikes ~125lbs up some decent hills though I wouldn't say it isn't without a lot of effort. Take off is a bit sluggish. I like the electric booster hub you have going there and vaguely recall the build thread. Have a link by any chance?

I gotta EZ QMatic with pulleys, so I'm not sure what the ratio is on them.

I'm 195 lbs as well and am at 34 MPH at 3400 RPM, with a aftermarket carb at WOT. Not worried about 0 to 20 mph as that is handled by the electric hub.

Here's the link.

http://motorbicycling.com/showthread.php?t=39823

 

[miked826]

Nice, clean build Mike. I have the same 97cc on my Felt with sprocket ratios of (10/30) x (10/44) = 13.2. It cruises fine at around 30mph and will haul my 195lbs plus the bikes ~125lbs up some decent hills though I wouldn't say it isn't without a lot of effort. Take off is a bit sluggish. I like the electric booster hub you have going there and vaguely recall the build thread. Have a link by any chance?

Thanks much. My next bike frame will be custom made following the same lines as the Felt MP/Slater frame, only it will be much taller. It will be able to hold ANY size vertical head engine using the exact same easily available motor mount. No welding skills or custom billet mounts will be needed. It will also be able to hold massively wide moped/motorcycle tires. That is my current mission in life. LOL

 

[Harold_B]

Thanks again for the link. Nice build and build thread. Documenting the challenges along the way are certainly appreciated. I'll be putting the electric hub idea in my hip pocket for now so to speak, too many other changes and priorities taking up available time and cash. Snow is in the forecast so I have plenty of time to think about it!

 

[miked826]

Thanks again for the link. Nice build and build thread. Documenting the challenges along the way are certainly appreciated. I'll be putting the electric hub idea in my hip pocket for now so to speak, too many other changes and priorities taking up available time and cash. Snow is in the forecast so I have plenty of time to think about it!

No problem. I just saw your Photobucket album and that red Felt you got has to be one of the most complex motorized bicycles I've ever seen. You must have the patience of a saint to create something like that. How long did that one take you to build...... in man hours?

 

[Harold_B]

Well, I'm definitely no saint but I have been pretty determined to get the bike finished in a way that at least comes close to my concept. If I ventured a guess on man hours it would be between 600 and 700, perhaps a touch more over 11 months. My wife thinks it was a lot more. The time and complexity are probably a product of my wanting a lot of electrical junk running without having to charge, not being able to weld so a lot of fasteners, and wanting to make as much for myself as possible like the jack shaft. That would be the rebuild hours since I took it down to the frame. Thanks by the way for taking a look!

 

[miked826]

Well, I'm definitely no saint but I have been pretty determined to get the bike finished in a way that at least comes close to my concept. If I ventured a guess on man hours it would be between 600 and 700, perhaps a touch more over 11 months. My wife thinks it was a lot more. The time and complexity are probably a product of my wanting a lot of electrical junk running without having to charge, not being able to weld so a lot of fasteners, and wanting to make as much for myself as possible like the jack shaft. That would be the rebuild hours since I took it down to the frame. Thanks by the way for taking a look!

You are the Felt Master for sure. Your Felts look factory made. I miss my fenders after seeing your red Felt. They both broke off one by one and I just gave up on them and tossed them after reading some horror stories on here. I too have no welder or the skill to use one.......yet.

 

[Harold_B]

Well thanks again but I have not so much mastered the Felts as just come to a reasonable arrangement with this one. I ditched the Felt fenders and went with Nirve but modified them a bit and then made my own brackets. The idea of tasting pavement because I like the look didn't sit well with me either. I have a little more I'd like to do on the rear but the front is solid enough that a decent sized kid could stand on it. The complex / cluttered looking brackets look at home on my bike though or at least I think so. Believe it or not one my goals when I rebuilt the bike was to simplify and de-clutter. Oh well, I guess it's a fair representation of what's in my head. Clutter.

I really like the look of the electric rear hub. Certainly something for me to consider.