[CAM2]

Finally got a comp reading on the second engine. 65psi. Pretty much toast. If it does run, it wouldn't very well. It definitely felt like less than the first. This one will be the one I will play around with, mod wise. Provided the cheesy Chinese "chrome" bore is worth messing with. I know I will need to replace the crank just to get away from the electric start. This one also has a two shoe clutch were as the first one is a three shoe. Both are shot though as is the drum on the first. The previous owner ran it to the point to where the friction material is gone and it was just the bare aluminum on the drum. I won't mention the "milk" in the gear box. (wait, I just did )

you dont need to replace the crank to get rid of the e-starter...theres two ways...one way is to gut it and the other is to eliminate it.....The pawl works either way.........The difference is only the length of the bolt needed to attach it

 

[ThumpLump]

Thanks, flattie42. I got it apart but, when I did I realized that the crank end on the side is tapered for the electric start armature to mount, as opposed to flat with a external threaded end like the pull start only version. I know I can get around it a couple ways but, neither are worth the effort. It would be easier to replace the crank with one for a pull start only end. (I wrote this while you, CAM2, were posting your last one)

I am going to see if I can drum up some local interest and see where it leads.

A Polini is out of the question. I looked at the prices and I could race my either my Yamaha SR500 or Suzuki vintage roadrace bikes for the same or less. For that matter, I could finish my '86 Yamaha FZ600 project. It's getting a XS650 engine, like this......

 

[EPR]

Wow, have not seen a Yamaha twin cyld 4 stroke for decades, my friend had a 650cc I believe, they copied the Honda twin engines.

 

[ThumpLump]

..... they copied the Honda twin engines.

Not really. The Honda twins had a 180 degree crank (one piston at the top and the other one at the bottom) were as the XS650 Yamaha had a 0 degree crank (the pistons went up and down together). The only thing I can think of that Honda and Yamaha twins had in common were two cylinders.

The XS650 line started in 1970 with the XS1.

 

[swheels]

Before I get to deep into all of this, Are there any active racing orgs in the south east US? Searched SEPRA and SEMRA for a website and came up empty.

Those org dissbanded some time back. But there are still plenty racing to be had around us. There's 2 tracks not far from fayetteville Nc. Though the tracks are located in Sc. Then there's some trackdays that go on at V.I.R. in Va. I had to join faceless book to keep in the know. But the track in Elgin Sc holds the most races and trackdays that's the closest to Nc.(depending where you live in Nc)

 

[ThumpLump]

I am looking more for just beating around local parking lots. I have already had my fair share of traveling in my lifetime. I turned down Dunlop tires, traveling to all the Camel Pro AMA races back in the '80's, for the same reason.

 

[CAM2]

Thanks, flattie42. I got it apart but, when I did I realized that the crank end on the side is tapered for the electric start armature to mount, as opposed to flat with a external threaded end like the pull start only version. I know I can get around it a couple ways but, neither are worth the effort. It would be easier to replace the crank with one for a pull start only end. (I wrote this while you, CAM2, were posting your last one)

I am going to see if I can drum up some local interest and see where it leads.

A Polini is out of the question. I looked at the prices and I could race my either my Yamaha SR500 or Suzuki vintage roadrace bikes for the same or less. For that matter, I could finish my '86 Yamaha FZ600 project. It's getting a XS650 engine, like this......

Nice ...Its shaped a lil like my old YSR......




If you think the Polinis are expensive look up the DM's and the Phantoms...Theyre $5 and $7 g's........

I have an 85 VF1000RR v4 in near mint condition I bought at an estate sale for $500.00 w/2122 original miles.....Plans are to fuel inject it and give it a modern twist......Til then it sits safe n sound....

 

[ThumpLump]

I have an 85 VF1000RR v4 in near mint condition I bought at an estate sale for $500.00 w/2122 original miles.....Plans are to fuel inject it and give it a modern twist......Til then it sits safe n sound....

Want your money back?

I wouldn't touch it. Collectable to a degree.

 

[swheels]

I am looking more for just beating around local parking lots. I have already had my fair share of traveling in my lifetime. I turned down Dunlop tires, traveling to all the Camel Pro AMA races back in the '80's, for the same reason.

I can do either or both fun for me. There's another member on here from Nc that will be up for some parking lot bashing/racing also.(jrock22)

 

[ThumpLump]

Been painting and working on assembling the chassis. Frame weld are CRAP! Need new steering head bearings. Need to figure out something for handlebars. Straighten one side of the original ones or do something different. Different being aluminum mountain bike handlebars and clamp down through the steering stem.

The better of the two stock motors will suffice for now. I just want to see what I have when it's all together and going.

 

[ThumpLump]

Any suggestions for a pipe? The stock exhaust I have for this thing is a joke. Single tube bend 90 degrees with what I would loosely call a "silencer" on the end. It's an upright piston port engine. I'm thinking, if nothing else, get a stock pipe for the newer Cag and modify.

 

[EPR]

You need an over the head Fatty Pipe, if you can find one, seen them on eBay or Amazon under 43cc 49cc pocketbikeparts about $60, and a Walbro WT-813 with boost bottle intake. See photos

 

[CAM2]

Any suggestions for a pipe? The stock exhaust I have for this thing is a joke. Single tube bend 90 degrees with what I would loosely call a "silencer" on the end. It's an upright piston port engine. I'm thinking, if nothing else, get a stock pipe for the newer Cag and modify.

I had to make my pipe custom for mine.......I used an x1 revpipe w/pitbike 4 stroke 1 1/8"ID head/lead pipe



You may get lucky and get one of these to fit.........

jetpro for a sidecar racer....



X7 fatty pipe.........







Eventually I got tired of scraping the footpegs at even at the slightest of angle so I chopped off the engine plate and welded in a reeded engine to raise the footpeg height a couple inches which still wasnt good enough so I sold it for a $175 slapped together with junk parts and a pretty new $20 bone stock mildly modified 44mm bore engine all busted up like this......I bought the cag running for $40 bux and slapped the highly modded 49cc piston ported engine on my homemade r/c buggy

 

[ThumpLump]

Sounds like the Fatty pipe is the best way to go. Though, with some cutting and welding, I should be able to get most anything to work. I'll use the stock POS exhaust at first, just to see if everything is working and worth putting more $$$ into. No boost bottle though. Yamaha tried them back in the early '80's, known as YEIS (Yamaha Energy Induction System). Many aftermarket companies followed suit with their own version. After a few years of independent testing, it was widely disregarded and considered next to useless. Yamaha also quit using them after a few years. On the surface, the theory sounds good. It's when you look deeper into it and the principals behind it (Helmholtz Resonator), you will understand why a practical application on a 2 stroke engine is difficult and yields very little gain. It's all about perception. If you think it's a good thing, then your mind will tell you it works. But, the numbers simply don't back it up.

 

[ThumpLump]

Finally got three orders done and shipped to three different continents and can now get back to the Cag.

 

[CAM2]

Sounds like the Fatty pipe is the best way to go. Though, with some cutting and welding, I should be able to get most anything to work. I'll use the stock POS exhaust at first, just to see if everything is working and worth putting more $$$ into. No boost bottle though. Yamaha tried them back in the early '80's, known as YEIS (Yamaha Energy Induction System). Many aftermarket companies followed suit with their own version. After a few years of independent testing, it was widely disregarded and considered next to useless. Yamaha also quit using them after a few years. On the surface, the theory sounds good. It's when you look deeper into it and the principals behind it (Helmholtz Resonator), you will understand why a practical application on a 2 stroke engine is difficult and yields very little gain. It's all about perception. If you think it's a good thing, then your mind will tell you it works. But, the numbers simply don't back it up.

Those boost bottles for yamaha worked...I have one on my 83 yz80 and also my 2002 banshee w/421 stroker kit.......For engines w/o manual powervalves it definately works.......I tried both with and without...as you can see how it turned out...........

This thing is alchohol powered and pretty nasty,,,,add a 3-4ft long swingarm w/paddle tire to it and this thing can compete in hillclimbs............

 

[ThumpLump]

Perhaps they do work better on smaller cc than on full size bikes. I do know that they didn't last long on 125cc or larger bikes, power valve or not. At that point in time (early '80's) I had outgrown smaller bikes and didn't pay them much mind.

 

[ThumpLump]

So, I start to put together the chassis and behold, no front wheel spacers. No problem. Back onto the lathe and 20 minutes later, some brand new 6061 T6 aluminum wheel spacers. FWIW, at least on this old Cag, The axle dia. is 10mm and the spacer width is 10mm and 15mm on the disc side. Considering the condition of this old ratted out thing, I wouldn't carve those width numbers into stone. But they should be close if someone ever needs to make their own.

 

[ThumpLump]

I have to say, out of the thousands of bikes, hundreds of models, from the US, Japan, England, Germany, Italy and from, I'm sure, a few other places, these Cagllaris from China are the biggest dung heaps I have ever worked on. If anything aligns or is the correct size, it surely has to be by accident.

 

[flattie42]

You're right china cag bikes are POS's lol but there's a lot of room for improvement. I like to see it as the Chinese came up with a quick and cheap template for a build-it-yourself pocket bike kit, already assembled lol. Leaving it stock is just out of the question.