DAX 50cc friction drive

The Bicycle

http://www.walmart.com/catalog/produ...uct_id=4990073

Yes, I know it is a Walmart bike and all, but that darn seat is comfortable as all heak to me and it rides very well, and the added bonus of the very flat cruiser tires was nice.


The Friction Kit

http://www.bikemotorparts.com/kit.html

My second kit I have bought from him in about a year now. Customer service is excellent and he ships very fast. He threw in a free throttle and kill switch for the return business.



The Engine

http://www.thatsdax.com/4STROKE_ENGINES_AND_PARTS.html

After about a week's research on what would be best for me, I decided this was the engine. It is powerful, extremely quiet, and has a full 1 litre fuel tank for the longer rides. Engine starts on the first or second pull every time!


The Build

I came home with the bicycle and knew I wanted to go over all nuts and bolts and retighten them. And very glad I did as the front wheel axle nuts was hand snug on the forks! I knew the rear fender would have to come off so I removed the rear wheel and the coasted brake and took out the two screws that held it on. The bicycle frame itself did not have the (2) 5mm holes in it to support the bars, and I knew this buying it, but there was plenty of room to drill out a 5/16" hole on each side to bolt on the side posts for the kit. Out came the drill and the string to line up the two holes correctly, easily done.

Throwing the friction kit on was very easy as everyone knows. The kit itself came with the 1.25" one way bearing and shaft installed on it already! And I have a spare 1" roller as well.

The engine came very well packed in bubble wrap and packed in a ton of foam peanuts in a oversized box. Very nice work on packing Duane! Threw in about 11 ounces of oil and a bit of gas and on the second pull she came to life quietly purring away.

The 1.25" one way roller seems to wor very well. Even with the engine at an idle (clutch disengaged) and stopping on a slight hill with the roller depressed into the tire, the bicycle will actually roll freely down the hill by itself. Cruising at speed and letting the throttle go, I honestly can not feel any slowdown on the bisysle from the roller. Seems to work very well for me.

I am thinking as a future upgrade to this project to remove the 1 litre fuel tank from the engine and install a larger, maybe ~1 gallon or so tank onto the top of the friction channel for all day riding with no worries. If I do this, I am thinking at this time I will have to strengthen the front U bracket of the kit for the added 8 pounds or so. But, for now, I am averaging about 35 miles per one litre of fuel, which is plenty of me.


Now for the TO DO list...

Must fab up a stronger L bracket for the front fender as it was vibrating already while riding.

Must install a front brake for safety reasons as the coaster brake has less then stellar performance.

Must reroute the throttle cable for a cleaner look and trim it down to size a little better.

The down tube is kind of egg shaped so I need to find a way to carry a fuel/water bottle.

Seriously thinking of looking into adding mirrors on the bike for safety. I was so enjoying my first ride, I did not even know a car was following me down a small sidestreet for a good 1/4 miles or so.


With having a few installs under my belt of the HT setups, push trailer setups, and friction drive setups... the friction drive setup is pretty well the easiest and most full proof way to go in my opinion. It rides very smooth for me and very very little in the way of vibrations.

Attached pictures show more details and the 5/16" holes I had to add to the frame...

Regards,

Steve

 

[TREEWK]

S Beaudry, Nice Clean Looking Build. I Too Started With Jb1970ny. Very Happy With Him. Just Run Two More Supports Off The 5/16" Bolts By Your Axle To The 3/8" Pivot Bolt. That Will Keep The Channel Nice And Level And Support The U Bracket, It Will Look Neat And Support A 5 Gallon Tank!! Lol. I Recently Bought 2 Dax Titans. Mounted Then With Cvt Belts Drives. I Bought 10 Of The 1 1/4" Freewheel Rollers. There Really Is No Drag Without Them. I Think A Larger Roller With The 50cc Would Be Nice. Nice Build, Glad You Are Enjoying It. Ron Ps The Added Supports Would Create Triangles, Nothing Stronger Than That.

 

[Happy Valley]

Spec for load, that simple, nothing else needed. 1 1/4" strapping for the U bracket carries the load, 1' strapping you get torsional flex. The difference in price between the two bar stocks is nominal, that's my gripe. Dave Staton worked this out years ago. It's about keeping the drive spindle 90 degrees to the plane of the wheel.

 

[s_beaudry]

Beaudry, I think BMP sells a synthetic 1.50 roller for your kit as well as a smaller 1in roller for hill climbing. The only issue is that only the 1.25 has the freewheel in it from what I gather on their website. A little engine braking isn't always a bad thing especially with a large roller unless you're planning on coasting down mountains. Better brake pad life is another plus.

Sir Jake,

I do like the freewheeling of it, but do appreciate an engine brake and especially since I only have a coaster brake at the current time.

I was thinking of trying out the 1.5" roller and seeing how it performs. I am not much for the higher top speed, but I would like the engine at a lower rpm and a quieter ride if you would.

My normal cruising speed around town is ~ 15 to 18mph and sometimes in the open I will hit ~25mph or so, but I am more of a slow and steady kind of guy that a top speed cruiser.

Next time I swing by the BMP site, I may just pick one up and try it out...

 

[SirJakesus]

As far as the free wheel roller, I have that on my bike now. I have not tried the 1" roller. James from BMP tried to explain to me the advantage of the free wheel. I thought I understood him, but with a centrifigal clutch, I don't see that it will make much difference. James says it will, for me to try both and see for myself.
As far as engine braking, there is none with a centrifigal clutch. Brake pads are cheap. You just have to be responsable and keep up with your bike for safety reasons ! I hardly ever use gear box in my cars for slowing down. Again, brake pads are a lot cheaper and easier to replace than clutches and other fatigued things associated with them.

The thing is the freewheel MUST help a lot for coasting since the centrifugal clutch only disengages at a very low RPM on most engines. I can feel on my TLE and RS staton setups that my speed has to dip down to 10mph or so before the engine finally gets disengaged from the roller. This is more important for steep descents where you may want to be a nutball and hit 40mph than just wanting to freewheel and pedal through an area without raising the roller. It must make for a very smooth ride for sure.

Don't get me wrong, I get the feeling that you think I'm bashing on the BMP kit in favor of staton... I'm not. I'm interested in his kits myself BUT I'll wait until they're more refined and time tested. He has some good ideas about spindle swapping and easy engine compatibility.

Ride that thang!

 

[TREEWK]

They Are Both Great People. I Bought My Freewheel Rollers From A Ind. Liquidator. I Think My Drive Shafts Are A Hair Under .500" And The Rollers Lock Up, Don`t Free Wheel. They Are The Same As Bmp. I Bought 1/2" Shoulder Bolts And Cut The Allen Heads Off. The Cheaper Bolts Are A Hair Undersize. I Have Staton And Bmp Brackets. The Extra Brace Is A Nice Addition For More Than 1 Reason. Imho. To Each His Own. They Both Have Proven Products. I Have Slime Tubes In My Friction Drives, But Am Hearing Of Tires Exploding From Heat. In The Future I Will Use The Tuff Plactic Like Liners. We Have Not Had A Flat Yet. Until Recently Few Friction Drives Had These Larger Cc Engines. I Started With 49cc And Like Them. We Just Go Easy On The Throttle When Starting. Have Fun, Ron

 

[Porkchop]

Guys, I hope wer're not getting off topic and taking over beaudry's thread, but you are loosing me about the centrifigal clutches and engine braking. I was running a 50cc Harbor Freight engne until tonight. I just installed a new Honda GX35. Doesn't matter what my speed is, when I let go of the throttle, both engines idle in about 2 or 3 seconds, and of course disengaging the clutch. I understand how you can aquire engine braking with a centrifigal clutch at partial throttle with a non free wheel roller

 

[SirJakesus]

Perhaps you have higher RPM engaging clutch springs than the ones that are installed with a staton kit.. In fact now that I think about it my RS kit would disengage very soon after I let off the throttle when it had less than 4 hours on it, however when it started to get broken in the clutch stayed engaged until the bike was around 10mph just like my Mitsu TLE kit...

I don't think beaudry minds, all of this is in reference to the BMP kit and friction drives in general. He'll probably post new pictures with a larger roller or with the left side sag issue solved and -BAM!- all of this chatter will be right on topic

 

[Porkchop]

You might be right now that I think about it. I would imagine after quite a while the clutch springs get weak. I remember when I was a kid, the springs on our mini bikes would get weak with age and use. I have only around 100 miles on my bike, so a little to early to tell.

 

[Hawaii_Ed]

Nice build, but get some brakes on it soon

 

[wilbur]

Sir Jake,

I do like the freewheeling of it, but do appreciate an engine brake and especially since I only have a coaster brake at the current time.

I was thinking of trying out the 1.5" roller and seeing how it performs. I am not much for the higher top speed, but I would like the engine at a lower rpm and a quieter ride if you would.

My normal cruising speed around town is ~ 15 to 18mph and sometimes in the open I will hit ~25mph or so, but I am more of a slow and steady kind of guy that a top speed cruiser.

Next time I swing by the BMP site, I may just pick one up and try it out...

So is 25 your top speed?.