what did you do to your motorized bicycle today?

[mogollonmonster]

Got my new mag and CDI from Dax today, my bike has never run so smooth! I've got to do a speed run after work tomorrow, once I put the speedo back on, I've already got the 44t back on, for now.

My used plastic fenders came off in pieces, so it's time to find a new set of mud catchers... Maybe not... Also tomorrow I'll finish up my new rack, which is an old one I've cobbled some baskets to, we'll see how it works out. Think I'll try out a dynamo head light, I'm not yet ready to wire a battery into my lighting system, but ise thinking on it. New breaks will probably be my next investment, u figure I've gotten just about all the use out of these I can. It is no longer possible to skid a wheel, and levers, return springs, heck everything has just about had it. Not sure if I'll go to a bike shop and have it Johnny on the spot, or go online, and pay a decent price...

 

[Tony01]

Removed my motor last night, shaved the head another .005" for a total of .020", cleaned all the carbon buildup off, lapped the valves in and set the lash, which was off by only .001" on the intake. Also ported/polished the ports some more as I didn't do such a great job last time. The exhaust port is sooo smooth now, threads cut down cause I'm using a bolt on header. Decided to start the painting process, masked off all parts where needed and finished painting the head and cooling shrouds, currently finishing the primer coats on the block.

 

[Tony01]

And the block is painted. I decided to paint the head the same color, had it grey but it just didn't look right.

 

[BOYGOFAST]

Another important thing is having enough power to stop the bike once it is set in motion .

 

[BOYGOFAST]

Good picture of a worn disk,they only give you a few thousandths on those but when they heat up I'd bet they fade or bend new .My coaster brake gets hot in a few minuets and won't work much better but has not broken yet.

 

[mogollonmonster]

Well I pulled the head today...

After more than 2800 miles, the cylinder walls themselves look pristine... The crosshatching done in China looks untouched... Top of piston and combustion chamber are filthy and coated in carbon of course, as I just can't seem to lean it out. Once I've got a second base gasket in hand, I'll pull the jug and clean up the casting slag in the exhaust port. The slag is reducing the port size by approximately 30%, and I believe it to be the cause of my over rich issues.

 

[mogollonmonster]

So yesterday, I bought some gasket maker, needle files and a fresh pair of big girl panties, pulled my jug, and finally cleaned the slag out of my exhaust port.

A note to all fellow patrons of Ace hardware. General brand, carried by my local ace is junk. I wore out the round and half round files in no time at all. Either of the other two sets at my ranch would be untouched, these craptastic files are almost smooth after their battle with the best beer cans China has to offer. The handle and case that came with the set are of higher quality than the files.

Beyond all that, this was the first port work of any kind that I've ever undertaken. I hope I didn't screw anything up lol, I made sure to bevel the edges to avoid ring snag, and only made the opening of the port match the port itself.

I've got to remount the motor into Tanglebones and wait for the exhaust gasket sealer to set up. Stand by for testing.

 

[mogollonmonster]

It worked!!!! Runs much smoother now, almost no fourstroking at all, just a little before it warms up. It definitely leaned out a bit too, no more flat spot in the throttle, and my plug looks good. Lots more power throughout the rev range, but especially down low. I was given another stock exhaust, this one has a significantly longer header, which will clear the pedals better, and should help the lower end a little, I'll dink with it later.

 

[tgaydos]

It worked!!!! Runs much smoother now, almost no fourstroking at all, just a little before it warms up. It definitely leaned out a bit too, no more flat spot in the throttle, and my plug looks good. Lots more power throughout the rev range, but especially down low. I was given another stock exhaust, this one has a significantly longer header, which will clear the pedals better, and should help the lower end a little, I'll dink with it later.

very nice man, getting your port job right is always a good feeling. what kind of exhaust are you changing to?

 

[DaveC]

So yesterday, I bought some gasket maker, needle files and a fresh pair of big girl panties, pulled my jug, and finally cleaned the slag out of my exhaust port.

A note to all fellow patrons of Ace hardware. General brand, carried by my local ace is junk. I wore out the round and half round files in no time at all. Either of the other two sets at my ranch would be untouched, these craptastic files are almost smooth after their battle with the best beer cans China has to offer. The handle and case that came with the set are of higher quality than the files.

Beyond all that, this was the first port work of any kind that I've ever undertaken. I hope I didn't screw anything up lol, I made sure to bevel the edges to avoid ring snag, and only made the opening of the port match the port itself.

I've got to remount the motor into Tanglebones and wait for the exhaust gasket sealer to set up. Stand by for testing.

It was probably the hard chroming that took out your files. Did you check the smoothness of the edge leading from the cylinder? It's possible that a burr from the filing could cause a problem with the ring after a while. Drawing Emory cloth from the inside of the cylinder out of the port will remove any possible burr. Work it from the bottom and from the top, breaking the edge.

 

[mogollonmonster]

No Dave I think it was the Taiwanese scrap iron they were made of. I tried one out on a chunk of scrap aluminum with the same results. The files just suck is all, no biggie. I did use some emery cloth, everything worked out beautiful.

Getting the Dax banana pipe...

 

[DaveC]

No Dave I think it was the Taiwanese scrap iron they were made of. I tried one out on a chunk of scrap aluminum with the same results. The files just suck is all, no biggie. I did use some emery cloth, everything worked out beautiful.

Getting the Dax banana pipe...

That's just sad, I hate bad tools and there's a lot out there these days and improperly hardened files a complete waste of money, time for a good set

 

[mogollonmonster]

I have a really good set, and a "junk" set, both are much better files. Regardless, job is done, bike runs better than ever, so I'm satisfied. Now I know for the future. This time, it was either buy a set or ride 50 miles for what I had, next time, I'll take the ride. Trash tools being what they are, I thought I'd warn my fellow customers, as I know many of us shop at ace quite a bit.

Hoping to place my order with Dax tomorrow afternoon, for the expansion chamber, and possibly other goodies if my budget allows. As money comes in, ill be starting a second build, thus, Tanglebones, with all his miles, becomes the test bed. The cylinder looks pretty good, and I'm happy with my port work. I believe the upper con rod bearing is going, but that's just a guess from the upper end noise. I know these ChinaGirls make a lot of racket, but this intermittent disturbance in the force sounds like a bearing. I didn't have the courage to pull the piston off, as I don't have another bearing on hand, Dax has them so no biggie there. I'm putting serious thought into notching the piston skirt at the intake port. Any thoughts on that?

 

[YesImLDS]

On my builds I put the piston at tdc mark everyThing blocking the intake port on the piston with a sharpie then chop all that off. Less rotating mass and more intake timing that isn't excessive.

 

[mogollonmonster]

That was exactly what I planned to do, so I take it you approve sir? I won't be performing that task till a new upper con rod bearing gets here.

 

[YesImLDS]

That was exactly what I planned to do, so I take it you approve sir? I won't be performing that task till a new upper con rod bearing gets here.

I have done it to every piston I've touched with these engines! It's hard to over do it and have bad effects. Some people do half moon shapes, but I just did a straight line across the piston with no problems at all.

 

[Tony01]

Custom made a 3-stage header. No bends, the first bend is composed of the first pipe cut into angled pieces, welded, then ground smooth. And did my header brace!! Every exhaust I have had so far shook itself loose and broken.

 

[MEASURE TWICE]

Is that a tube at the top of the head bolts maybe? It melds with the exhaust tube for support?

 

[Tony01]

Is that a tube at the top of the head bolts maybe? It melds with the exhaust tube for support?

Yep. It's slightly larger tube than the primary pipe, I cut it in half lengthwise and flattened the end with some grinding to fit, and then cut a d-shaped flat at an angle into the back end of it to give a gripping surface for the hose clamp. It feels very solid and nothing has loosened up in 2 heat cycles (driving 15min and letting cool).

I'm determined to get the most out of this motor before I upgrade. Next mods:

1. Grind the plastic camshaft (have extra). Remove ~.030" radius from base circles and weld/.030" onto the lifters... Get some more lift - CURRENT LIFT is .157" from measuring the cam
2. Upgrade to a larger carburetor with a straight shot intake.. I'll get rid of that s-manifold I think I'm losing power cause of it
3. Advance timing 4deg- going to fabricate a plate that moves the magneto approx .220"
4. Increase compression further to where I have .020" valve clearance, maybe open up the transfer into the cylinder in the head

Bike mods- new design 2-speed (delete one js, delete two chains)
Full suspension


The current 2-speed while works, is difficult to adjust and keep it aligned. It's out of alignment frequently and I get fast wear in my chains and the power loss is noticeable on the top end. It isn't strong enough but I've proven the concept on this bike. Currently tops out around 45 on level ground. I wanna bump that to 50. It's still a legal displacement and hp for CA Mbs.

 

[mogollonmonster]

Ordered parts today. Wrist pin bearing(needed), rings(just to have around), and an RT head(because I can)

I'm hoping with the expansion chamber pipe and "alleged" high compression head, I'll get enough power to run a slightly smaller gear, maybe a 40, doubtful a 36, too many hills for that

Since I'm not making the long commute, have a much increased income, and will have a second motor soon, I've decided to aim for 35. My top speed so far is 32.5mph, so it's not too much to ask,