Honda 11 HP "motorcycle" build!

[l0ll00l]

So a while back, my friend and I took it upon ourselves to construct a vehicle out of spare scrap iron and an 11 HP Honda engine we removed from a pressure washer with a burnt out pump. I'm sure those of you familiar with welding will quickly spot my HORRIBLE welds, and nonsensical geometry of the bike, but I've since learned a lot, both in welding and engineering, so the next go-round won't be so bad.

We have recently decided it was time to completely re-build the bike, using a new design that we created, that will be notably stronger and less awkward looking.

Anyway, I will let the pictures speak for themselves, but will be keeping a thread(likely this one) updated with the new construction that we plan on starting this Saturday the 14th if anyone shows any interest.

Also, the bike is capable of roughly 49 mph. While testing the bike, someone felt it was necessary to call the police and report "A strange vehicle making a racket on their street." Haha. The cop was actually one of the very few down to earth officers I've met, and after closely inspecting the bike, told me he would be willing to clock my speed if I wanted. I think he was more interested in it than I was!


Picture of some of the first welds on the frame rails.

Rear view of the completed frame. We happened to have an old bike lying around, and promptly chopped off the front end, as I was not particularly looking forward to designing a proper front end at the time.

You can also see the brake rotor and rear sprocket mounted on the rear axle.

Side shot of the completed frame.

Fitting the motor and welding on motor mounting plate.

This picture shows the jackshaft needed to transfer the power to the other side of the rear tire. Looking back, I could have shifted the engine over by an inch or two, and eliminated the jackshaft altogether. I’m really not sure what we were thinking.

Also shows the cover I built for the clutch/chain at the engine, the hydraulic brake caliper, and horribly welded exhaust.

And finally the completed picture. Don't mind the miscellaneous parts/metal/soda cans strewn about. I was excited and wanted to drive it.

The bike handles decently. I won't lie, it isn't nearly as I had originally envisioned it, but I hope to correct that, with a smaller front tire, a proper front steering setup, and I hope to build the frame to enable a drive train without a jackshaft.

So let me know what you guys think of my little hobby/experiment! If anyone seems interested, I'll make sure to keep this thread updated with pictures of the new build!

Also, small word of advice; Don't ride a 150lb bike with a skinny bicycle tire up front when the roads are wet.

 

[Jerryburger]

COOL BUILD!.... and OUCH! Bike front ends are hard to pass up... they're a lot stronger than they look.

 

[Scorch3]

Thats a cool... thing. I would definetley be interested in seeing your newer better version. Are you going to stay with the same general shape and design only more refined?

 

[jr dragster T]

Ouch!

 

[l0ll00l]

Thats a cool... thing. I would definetley be interested in seeing your newer better version. Are you going to stay with the same general shape and design only more refined?

Well that's our dilemma. I'm all for the simplicity of basically making a narrow 2 wheel gokart (like this last build) only with wider frame rails to avoid the weak design it currently has, where it is wider in the rear, but I'm also toying with the idea of welding up a more traditional motorcycle frame where you're pretty much sitting on or behind the engine.

Both my friend and I rather like the feeling of flying down the road doing nearly 50 mph, and about 3 inches from the ground, but I'm also interested in trying new designs.

What are you guys' opinions? We are open to ideas, but are pretty much planning to attempt to use as much from the old build on the new one to minimize costs. (Brakes, Axle, Rear wheel, etc.)

We've considered making a lightweight road kart, but funds won't currently allow for the cost of 3 more wheels, new axle, new master cylinder(current is handlebar mounted), and the other odds and ends needed to make it into a kart.

Any input is appreciated!

 

[r_chez_08]

that engine looks dangerous, you better ship to me for testing
(i like 11hp hondas v mutch)
btw, looks great fun!

 

[l0ll00l]

So! After finally getting some time to get working on the rebuild, my friend and I made some progress today!!

The welds are sloppy, but very solid.

First, a picture of the old build after weathering in my friend's back yard.

The brake rotor.

The 50T sprocket. I have no idea why we used such a small sprocket. The engine handles it fine, but the clutch does slip a little more than I'd like during acceleration. Once it gets to around 10 mph, it doesn't slip at all though.

We cut off the last 8 inches of the old frame rails that have the rear bearing carrier mounts welded too them. I couldn't find any at Northern this afternoon unfortunately. We slid in 8 inch square tubing, slightly smaller than the new frame rails. 4" in the tubing with the bearing carrier mounts, and the other 4" in the new frame rails. The axle was flipped over, so that we could eliminate the need for a jack shaft. We welded the two pieces together on each side, with the smaller tubing inside, and the rails are both as solid if not more than, the rest of the rail. The sprocket will be moved closer to the frame rail tomorrow when we work on it some more, to help center the engine better.

With that done, we moved on to the front fork. Being that it originally had a suspension, it had smaller tubes at the top that slid into larger tubes at the bottom. We cut off the bottom half, leaving only about 6-8" of the small tubes. We then slid 8" pieces of square tubing over them, and welded both at the top(to the lower plate) and inside the bottom, to the circular tubing. I wasn't sure how well that would work at first, but it is VERY strong. Next, we cut two 16" pieces of square tubing, and welded those to the outside of the 8" pieces, with a small piece between the tubes to add a little more strength. There are 6" pieces of angle iron welded at the bottom, with 3 inches extending past the ends of the fork, so we have something to mount the axle to. Didn't want to compress the tubing when tightening the inner and outer lock nuts.

Yes, I know the welds are ugly, but again, very solid. Ground down the welds, and threw on a quick coat of rustoleum to keep it from rusting before we get a chance to actually paint it.

We were beginning to run out of daylight, as we had a kind of late start, so we decided to prop up the frame, set a board on it, set the engine in place, and rested the fork on it, so we could mess with it and get an idea how we want the frame set up.

This morning, we'd planned to do almost the same thing, with the "recumbent look"; engine behind us, with the seat mounted directly on the frame rails, but decided to do it a little differently, and hopefully better.

We are adding two pieces from the rear frame tube, at an angle, forward, and up over the engine. The seat will rest slightly above and forward of the engine.

The front end will have all the ridiculous looking tubing cut off, but will remain pretty much at the same angle as it is now, and probably just a few inches further forward than it is in the picture.

And finally, a picture of my friend sitting on it. We are welding pegs both up front, and in the rear, near mid engine, so that for top speed runs, we can tuck our legs back, and lean forward so that we aren't creating so much drag.

Well that's it for today! We will be working on it again tomorrow, and hopefully get it running! If so, there will be more pictures and hopefully a video or two.

Let us know what you think! We're excited about the new design, and really hoping this turns out to be another reliable cruiser!!

 

[l0ll00l]

that engine looks dangerous, you better ship to me for testing
(i like 11hp hondas v mutch)
btw, looks great fun!

Wow, serious? I'll box up that engine, and have it shipped out first thing Monday morning!!!

I love Honda engines too. That is by FAR, the smoothest running, most reliable and torquey engine I've ever used. With the "custom" exhaust pipe and muffler, it has a nice low smooth idle, but when you get on it, it sounds a lot like a real motorcycle! I actually just bought a quart of Royal Purple engine oil, and plan on using a better filter setup to let that engine breathe better. Also plan to remove governor and install stiffer valve springs in the near future. Might even do some porting/polishing if time allows.

 

[SpyGuy]

Wicked machine! Keep us informed on the build.

 

[ZnsaneRyder]

High Horsepower and cold steel!

 

[Russell ATV]

I worked on a similiar build with a Low Rider mini bike style. I think you found out the same problem. When you and bike share a very low center of gravity, it is difficult to lean and gain balance, especially at low speed. I think the seat above the engine will solve that problem.

Russ Barrow
Russell ATV

 

[l0ll00l]

We got some more work done on the bike project today!

Caliper mounted on frame.

Decided to keep the majority of the old material intact, as welding to that thin metal is really difficult to get right. Cut the angle iron at the bottom a bit to give us the rake we wanted, and welded it to a cross member.

Got the engine mounts welded on, and chain installed. the whole rear end is a lot more solid than the last build.

Pic: welding the cross piece that the seat mounts on.

Attached the seat, throttle cable, brake lines and master cylinder.

We will likely be welding small pegs on the front forks to give a better spot to rest your feet. the front cross member is a bit too cramped for me to ride around on comfortably.

Still have a few other tweaks, including some engine mods, and of course some paint, but mechanically it's done!

This build has much better acceleration than the previous. Even from a dead stop, if you go WOT, the bike just PULLS! I'm still getting used to the feel of the bike before I attempt any top speed runs. around 45 mph is the highest I've taken it so far. Blipped the throttle, and there is still more there once I get the nerve!

 

[l0ll00l]

I worked on a similiar build with a Low Rider mini bike style. I think you found out the same problem. When you and bike share a very low center of gravity, it is difficult to lean and gain balance, especially at low speed. I think the seat above the engine will solve that problem.

Russ Barrow
Russell ATV

The new style is much better. I would have thought a lower center of gravity would be better, but in this case it certainly wasn't. Sure, it was fun being just a few inches off the ground, but I much prefer the new setup.

 

[jr dragster T]

That facebook link is to some little girls page? Bike looks good now!

 

[SpyGuy]

Might want to have something between you and the engine, but the rest of the build looks great!

 

[l0ll00l]

Might want to have something between you and the engine, but the rest of the build looks great!

Thanks! I'm still not sure what we're going to do about the back of the seat.

That facebook link is to some little girls page? Bike looks good now!

Haha, yeah. My girlfriend apparently had the link for her cousin's page copied, and I didn't grab the link from photobucket before hitting Ctrl V.

 

[l0ll00l]

Here's a video with a few fly by's, a walk around, and a couple take-offs from a stop.

Sorry for the poor quality. My friend used his cell phone as that's all we've got for now.

http://www.youtube.com/watch?v=ADYwgOqT03E

 

[jr dragster T]

Looks like fun!

 

[l0ll00l]

SO much fun! haha Now I just need to find a place to ride it! Parking lot kinda gets boring after a while.

 

[l0ll00l]

Just an update. We found a 54 tooth sprocket, and after extending the slots in the motor mount plate, got it mounted, attached the chain, and got everything tightened down. It's amazing how much of a difference 4 teeth on the driven gear will affect the final drive ratio! I'm glad we didn't go buy a 60t. The acceleration is perfect now! The clutch engages sooner, so there will be less wear on it, and it still has around a 38-40 mph top speed. More than sufficient for a neighborhood cruiser. We rode it for about 5 hours yesterday, and everything is holding up great! No broken welds, bent metal, or bad bearings. I'm still trying to get a hold of a real video camera that I can mount to the frame, and take everyone on some high speed runs!

We also remembered there was a generator sitting behind the shop, that has a perfectly good engine, but a bad coil. It's a 9HP Briggs and Stratton Vanguard OHV. We pulled it apart, to make sure there wasn't any water in the engine, as it had been sitting outside for a while, but everything was in perfect shape. It actually looks like a brand new engine! Sprayed a bit of carb cleaner in the intake with the filter off, and it fired right up! Only ran it for a second though. Really want to change out the oil before actually running it.

Anyway, all that to say, we're building a second one! Only thing cooler than cruising around on a completely scratch built bike that you made with your own hands, is cruising with a friend, both on bikes you built! Money is a bit tight, so this won't be happening next week or anything, but we will take pictures and keep the thread updated. =)

Here's a picture of the engine.