I bought this Kent bike for the frame, because it was inexpensive and I was going to upgrade a lot of the components anyway. I wanted it for the aluminum and not the full suspension. Popular opinion on the forum is the aluminum frames can't take the vibration associated withe Chinese engines. Then I've been reading airplanes are made from the same material in many instances and they vibrate a lot. I guess time will tell and steel frames break apart also. I gathered all the tweaks I could find on the forum (thanks guys) and applied them to this engine. Match ported and polished the intake and exhaust, removed the base cylinder gasket, lapped the head, changed the plug wire, plug, notched the piston where it blocked the intake port, lapped the cylinder. added SHA Dellorto, added tuned pipe, changed the hubs and rims (local bike shop did this part). The front hub brake is no better for short distance stopping in my opinion than the original v-brake. It may hold better over long distance stopping. I don't know. It was on sale and I thought it was cool so that is why it is on this bike. I've had it on another bike also. On the crank side of the shifter kit I changed to an 8 tooth sprocket. My other bikes bogged down in the higher gears and the power develops in the higher rpms with these engines I think. This engine runs and idles better than any other I've owned. It has more torque than I've ever had. It just keeps on winding. I rode this morning to find the top end mph. It was cold as !@#$%^&* little above 30 degrees. A couple of my neighbors blew the horn as they went past me. This was to make sure I know they see how crazy I am. Before my speedometer quit, froze probably, I recorded 39.4 for a top speed. I was pleased with this under the cold conditions. It may do a little better when it warms up and I can "tweak" it a little more.
Aluminum frame, 70cc engine, SBS, 39+ mph
- Thread starter i-paint
- Start date
Nice job.
You get a denser air charge with cold air. You can potentialy make the most power when it's cold and low humidity.
You get a denser air charge with cold air. You can potentialy make the most power when it's cold and low humidity.
Nice bike, very well put together. I like how the muffler pokes out the opposite side.
I'm sure that long intake runner helps with the low rpm torque, for sure. Nice fuel tank, did you make a cylinder yourself like datz did?
I'm sure that long intake runner helps with the low rpm torque, for sure. Nice fuel tank, did you make a cylinder yourself like datz did?
Another beauty!
You have developed a real talent for building in tight spaces. I always like your choice of parts. Lightweight, Strong, Great features. The drum brake may not seem any better than the rim brake but it will still perform well in the wet and it looks great too. Front forks are always nice but still easier said than done on a cruiser.
It sounds like you massaged that motor sweetly and it is paying you back in dividends.
You have developed a real talent for building in tight spaces. I always like your choice of parts. Lightweight, Strong, Great features. The drum brake may not seem any better than the rim brake but it will still perform well in the wet and it looks great too. Front forks are always nice but still easier said than done on a cruiser.
It sounds like you massaged that motor sweetly and it is paying you back in dividends.
That's some intake!
I agree that the drum brakes usually don't match rim brakes for stopping power but they more than make up for it with cool factor and wet weather effectiveness. Cheers
I agree that the drum brakes usually don't match rim brakes for stopping power but they more than make up for it with cool factor and wet weather effectiveness. Cheers
Re: New post for Aluminum frame, 70cc engine, SBS, 39+ mph
I have two new images to add. First, I changed to a dax engine that I took apart and "massaged" when I received it and I changed the pipe and sprocket on the shifter kit to a nine tooth. I rode it today and with 66 miles on the engine recorded 43.5mph on flat ground. I ran out of street and was in sixth gear. My chains rub in seventh and I haven't fixed it yet. I was pleased with this performance and think it will improve as the engine breaks in. The first engine was a "vibrator" that I've had on three different bike frames. It is a very strong engine but I can't take the vibes. The dax is much better, only vibrates noticeably at about 1/4 throttle.
The second improvement, to me anyway, is I powder coated my exhaust pipe flat black and it is holding up well. The first section of the pipe is high temp paint. I didn't think the powder coat would take that much heat as it is not high temp powder. I only masked off one width of tape behind the welded joint and thought I would just wirewheel the "over powder" off. It was difficult even with the wheel on the bench grinder. I left some on the bottom of the pipe and painted over it. It is still on there so maybe I could have powder coated the entire pipe. If I were going to do many of the pipes I would buy some high temp powder. Also I am setting up my oven to be able to powder coat the frame. The pull start cover, the bearing plate and clutch cover are high gloss powder but are difficult to see in this picture. The powder is amazing compared to paint.
I have two new images to add. First, I changed to a dax engine that I took apart and "massaged" when I received it and I changed the pipe and sprocket on the shifter kit to a nine tooth. I rode it today and with 66 miles on the engine recorded 43.5mph on flat ground. I ran out of street and was in sixth gear. My chains rub in seventh and I haven't fixed it yet. I was pleased with this performance and think it will improve as the engine breaks in. The first engine was a "vibrator" that I've had on three different bike frames. It is a very strong engine but I can't take the vibes. The dax is much better, only vibrates noticeably at about 1/4 throttle.
The second improvement, to me anyway, is I powder coated my exhaust pipe flat black and it is holding up well. The first section of the pipe is high temp paint. I didn't think the powder coat would take that much heat as it is not high temp powder. I only masked off one width of tape behind the welded joint and thought I would just wirewheel the "over powder" off. It was difficult even with the wheel on the bench grinder. I left some on the bottom of the pipe and painted over it. It is still on there so maybe I could have powder coated the entire pipe. If I were going to do many of the pipes I would buy some high temp powder. Also I am setting up my oven to be able to powder coat the frame. The pull start cover, the bearing plate and clutch cover are high gloss powder but are difficult to see in this picture. The powder is amazing compared to paint.
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would it be possible to get a parts/mods list from you. im in the middle of a build and i could really use some of those bit and pieces. carb, front hub, intake.
Where did you get this bike? Is it easily availble? Also, agree wtih Classic, besides internal engine improvements, what did you have to do to make it fit on the frame? Anything special? I'm always looking for a replacement bike for the Skyliner which is now ugly and doesn't fit an engine well and the Searcher has gone up 50 bucks in price.
Thanks,
Thanks,
Classic, donuts, Thanks for your interest. I bought the bike from K-Mart. It is a Kent Glendale. Ten pound lighter than a steel frame bike I have, similar in shape and size. I really had to remove a lot of the front mount to let it fit over the down tube. I formed a piece of thin aluminum to fit the tube under the mount. I cut the rear mount as short as I could. I mounted the engine in the frame using the rear mount but left it loose. After I put the piece of aluminum between the front mount and the down tube I put some JB Weld on the front mount and let the engine slide down the seat tube until it was resting on the aluminum piece. I tightened the rear mount to get the proper angle and let it dry overnight. I then removed the engine and fill in around the front mount and aluminum piece with more JBW. When you alter the engine mount as I did, be aware it can only be used on the bike you fit it to This bike has rear suspension (not very good, just a spring) You will have to use the Sick Bike Parts shifter kit. The carburetor I bought from Dellorto Direct. I made the intake from 3/4 tube and 1/4 in steel plate. I bought the rims from some guy on ebay. They had a three speed internal hub on the rear rim. I used it on another bike for a while. I had the bike shop to mount the hubs I have now in the red rims. The rear hub and cassette came from this bike. The front hub is a Sturmey Archer. I think it came from Jensen USA or bikesonline..
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looks and appears great...I to am building a aluminum bike...not as extreme as yours...my personal opion is that made in america aluminum is the way to go...dont know what you are getting from china...mines a gary fisher triple butted...built mounts, threaded and went thru th frame on both sides...its stable and smooth...im having trouble with fitting intake and card any suggestions would be helpful...building it for the winter build off so i have a while...hows the shift kit...?again youve done a great job////stay tuned...dennis
How was the 3 speed internal? I'm planning a bike similar to this i.e EVERYTHING done to it to make it the best it can be and should already be! My thoughts are to use a disc in front and 3 speed integrated hub and drum brake on the rear with a shifter kit.
drhoffer, The aluminum frame so far so good. raneyed, The tank is in the bag behind the seat. It is a xxxxxxxx to get out, but it is very similar to the one datz did for his bike. It is on this forum. milegajo, I didn't like the way the three speed shifted. It jerked even with backing off the throttle before shifting. I broke three bicycle chains before I switched to a #41 chain. It wasn't as smooth as the cassette.
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