This is intended to educational purposes only, so dont blame me if you blow your shizzle up.
My name is Donnie Archer I am a 30 year old Automotive/Metal fabrication teacher from Amarillo TX. I have written many technicle articles before for other board: including 3800pro.com.

Following this article plaese be aware that the sky is the limit for ideas, and swaps. This will give you a idea of what can be done. If you are just crazy there is a HH 250 in a town not to far from me with a turbo GSXR that makes over 250hp. But it super rediclous. He cant even take it off road.... way to much power for the weight.

Goal - to have a small framed buggy, such as a 150, that is able to handle very tight trails, hills, and turnes. AND to have very grunty low end able to climb or crawl over anything I decide.
AND
To have the total swap done for less than $600.00 - $1000.00 including buggy. INCLUIDING: Exhaust, ignition system, and motor.

I have chosen to use a 1979 Honda cb400 HONDAMATIC for a couple of reasons.
A. Its relativly light weight deseign, its not know for its tire smoking power, but it can hold its own very well. It being a two cycl deseign it produces more TQ than a 1cyl version. Most tech manuals show 30Hp for the automatic. 15Hp can be had by switching the heads and cams off of a manual version..... But I am not worried about that now.

B. Its an Automatic...... It does not use a belt or rubber drive units. It is very simular to a automatic transmission used in a car. It contains a TQ convertor, and clutch packs.

C. It also is know for its AWSOME reliability. The engines have a great heritage and can take a pounding. And because most of these engines are used in popular bobber and motorcycle builds, they have a relitively good aftermarket following.

D. MOST IMPORTANT. They use a CDI ignition VERY simular to our desein in the karts. They are very simple to wire and hook up. I will provide the Wiring diagram for this purpose. So those of you that choose to copy this article can follow it 100%

E. Low cost. I picked up two of these bikes for less than $250.00 bucks. I have been able to use misc parts off other Hondas as well.

This is intended to educational purposes only, so dont blame me if you blow your shizzle up.
My name is Donnie Archer I am a 30 year old Automotive/Metal fabrication teacher from Amarillo TX. I have written many technicle articles before for other board: including 3800pro.com.

Following this article plaese be aware that the sky is the limit for ideas, and swaps. This will give you a idea of what can be done. If you are just crazy there is a HH 250 in a town not to far from me with a turbo GSXR that makes over 250hp. But it super rediclous. He cant even take it off road.... way to much power for the weight.

Goal - to have a small framed buggy, such as a 150, that is able to handle very tight trails, hills, and turnes. AND to have very grunty low end able to climb or crawl over anything I decide.
AND
To have the total swap done for less than $600.00 - $1000.00 including buggy. INCLUIDING: Exhaust, ignition system, and motor.

I have chosen to use a 1979 Honda cb400 HONDAMATIC for a couple of reasons.
A. Its relativly light weight deseign, its not know for its tire smoking power, but it can hold its own very well. It being a two cycl deseign it produces more TQ than a 1cyl version. Most tech manuals show 30Hp for the automatic. 15Hp can be had by switching the heads and cams off of a manual version..... But I am not worried about that now.

B. Its an Automatic...... It does not use a belt or rubber drive units. It is very simular to a automatic transmission used in a car. It contains a TQ convertor, and clutch packs.

C. It also is know for its AWSOME reliability. The engines have a great heritage and can take a pounding. And because most of these engines are used in popular bobber and motorcycle builds, they have a relitively good aftermarket following.

D. MOST IMPORTANT. They use a CDI ignition VERY simular to our desein in the karts. They are very simple to wire and hook up. I will provide the Wiring diagram for this purpose. So those of you that choose to copy this article can follow it 100%

E. Low cost. I picked up two of these bikes for less than $250.00 bucks. I have been able to use misc parts off other Hondas as well.

Ok money spend so far.

Hammerhead 150cc twister - $400.00 not running.
1979 Honda Hawk - Cb400A "HONDAMATIC" - $150.00 no title.
1979 Honda Hawk - CB400 "5 SPD" - $50.00
2 UNI filters with 2-1/4 Openings $35.00
2 Exhaust Slips on - stock 2003 Honda cbr
Wiring diagram for my application from a friend. - $5.00
New coil for my 400..... priceless.... accually $10.00

Here we go, I will post updates daily.

Thoughts.... comments.....?

OOPS... double post

I didn't realize the automatic versions had a different head and cam. I'll bet that the auto's are set up to have more low end torque being that they are only 2 speeds. If thats the case you may want to leave the motor just as is cause the low torque will be more useful in the buggy than the top end horsepower.

I can't wait to see how this swap turns out. Who knows maybe my 400 engine will end up in my Twister.

Jamie

The only drawback I see is no reverse or do you have that covered.

Accually have that solved as well. As everyone know the reverse box on most stock buggies consist of a indipendent planetary gear system driven off the output shaft of the motor. Well, what I have decided to do is...... Because the reverse box does not know who or what is driving it.... I have taken the output shaft out of an extra motor. I chucked it up and - SHORT story.... I am machineing an exact copy of the output shaft, only on the side that is driven by the motor, it will be a 1" shaft that is 12' long, and keyed. YES IT WILL BE HARDENED So the drive from the CB400 will be to the shaft, that has pillow blocks on both sides of the shaft side. This will be fasten to the reverse box, just as it would be on the engine, and bracketed to the rear frame.... Thus I keep my stock reverse...

I chose this route for a couple of reasons.

A. The stock reverse box contains a set of hardened planetary gears. For those of you that are not familiar with a planetary gear system, go take a look at them on GOOGLE. They are incredible strong, and smooth. I believe that the stock planetary system will support up to about 50hp give to take.

B. Size, and ITS STOCK..... Which means it can be replaced relatively cheap. The size makes it ideal, and strong. able to be mounted in a variety of places.

C. Chain location. I also need a box that would allow the drive to go from the Drivers side, to the pass side so I would not have to flip the axle.

PICS coming soon I promise.... I just need to get some stuff done first...LOL....

I removed my old engine, and started to take measurments. It appears the cb400 will be no more longer, however it is about 5 inches taller. So here is what I have decided to do. I have removed the rear control arms, and sectiond them to accept a 6" section. I decided to go with a 6" for a couple fo reasons.

A. I felt as though a 6" extension was both sufficient and safe.

B. Safe Remember as you increase the length you also increase the stress put of both your buggy chassis as well as the shocks, and supports. I am going to reccomend that you get a longer/stronger set of shocks. As the stock shocks will be taking a much larger portion of the Stress/lever side. I am going to move up my stock shock mounts and see how they do. I will past a huge amount of pics demonstrating how to section and fill/extend the control arms correctly.

The CB400 will also have to be lowered in the rear cradle a little, to keep a min of clearance for a suspension rear end. I am utilizing the stock mounts from the front of the motor, and placing them on the rear control arms.

The I noticed I am also going to have to lengthen the stock brake lines, byt using a double ISO hard line in the middle of the seats to give me the extra 6". Also the parking break line. I will have to get it special made by a local shop. I might have to do the same thing with the reverse cable, and shifter.

thats going to be a great swap. cant wait to see the pics

Thanks BIGE. I go tthe steel from the local scrap processing. I was told that that was a china type steel size, and that exact size cannot be found in the states..... So I searched for a 12g wall as close as I could to the rear control arms, and picked a one that fits perfectly inside the width, but is about a 1/2'' to tall. SO My plane is to slide it inside the outer shell of the original controll arm, weld, and then drill and bolt a sectioning plate to the inside. That should make it incredible strong.... Any questions so far... The shaft will be finished within the next couple fo weeks. I am taking the camera tomorrow, and hopefully have the completed rear swing arm in place. With plenty of pics.


Donnie.

The correct way to section. When you decide whether or not you want to extend your swing arm, I reccomend that you follow one of these examples. Avoid butting flush ends together as this creats a very week joint. The first is the strongest type, however the third is also very strong. I chose the third because of the lack of available "same size steel". However make sure if you use the third type, make sure the center section fits TIGHT in the lower sections of the front and rear pieces. Here are some pics.

Here are some pics of the fit and welds. asa well as the progression of the extensiob...

What ya think? Looks twisted.....BAD