Cannonball Goes Totally Insane And Buys a CG!

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cannonball2

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Oct 28, 2010
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Colonial Coast USA.
Thanks IWW! Its another form follows function build dictated by whats left over in the parts pile.

Citi-sporter, I ran a horizontal line through the middle of the float bowl and I have a 2.5" drop. Should provide enough flow. Theres not even a hint of a hill here on the coast except for the suspension bridge south of town. I have my doubts if this thing would climb it anyway. I wound up with more angle in the carb Than I would have liked, but have seen builds on the forum here with a bit more. Guess I will see what happens.
I saw on a site(cant remember where though) adapters to run the more common Walbro carbs on the CG, which of course are pumpers. I have a Shimano 3speed hub which I have been saving for a build. Thought of using it as the jackshaft. If I was gonna run it with a CG I would opt for the pull start/centrifugal clutch engine to ease the torque loading on it and for starting of course.
 

cannonball2

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Oct 28, 2010
3,682
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Colonial Coast USA.
Am going to run a high quality BMX chain for the motors drive. Should have my thinner sprocket from DAX today, thanks for the fast shipping!
So I used my "newly included screw tool" as the Chinese hype calls it to remove the sprocket. Of course the threads on the screw tool and the sprocket required more than a casual introduction to engage. Once married and the extraction began it was soon obvious the extraction screw was too short which required a search for the right something to act as a spacer. Doesn't anybody in China check anything? Thats the "CG Life" I guess. Looks like a hammer fit to reinstall. Im loathe to hit anything on a CG as this has to be one of the most fragile engines I have encountered. The only time hammering is justified on one of these is when you have had enough!
Found a great location for the chain idler under the engine. No wonder the dastardly idler brackets constantly shift when mounted on the rear frame, they are sized for a 1" tube! Fits perfectly on the seat tube. If it works as hoped there will nail it down with the welder.
I have to comment at this point. I have been twisting wrenches as a job for over a half century now. These kits require a good deal of mechanical aptitude to understand/install. The neophytes have my sympathy. There are little hidden land mines all through these things. The one I found that could have been an issue if missed was the throttle cable was too short holding the throttle nearly to half. Remedied it by removing the locking barrel under the adjuster on the carb. I can imagine the surprise to some one upon first start up! I like a challenge and to tinker so this is right up my alley so to speak. Some kits Im sure could be bolt on and go, but I bet most aren't. Fortunately there is a wealth of knowledge on this site and people that are happy to share it. Please Noobs ask questions!

Editorial finished.
 

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cannonball2

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Oct 28, 2010
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Colonial Coast USA.
OK the build is basically finished and tested. Im pretty pleased, it runs! And pretty well at that. Im breaking it in on a 20:1 mix using ND 30wt motor oil. It started right up and ran cleanly no missing or anything. Seems really torquey. Will pull from stop if you feather the clutch a bit. Not only does it have the reed set up, but in order to space the exhaust, I added a finned spacer which is also supposed to increase torque. I have run it in the lower rpm ranges to take it easy on it, but did rev it a bit and its actually gets smoother as the rpms increase, at least as far as I have taken it. The overly angled carb runs fine. My biggest complaint is the primary gear noise, maybe they will wear in and quite down a bit. They are well lubed.
Since the wiring was too short for the kill switch to reach the engine, I went old school and added a ground clip. Works great. Bean can fuel tank set up works fine.
Bike rides and stops well with the coaster/BMX side pull brakes. Its a pretty light build too. I easily flipped it over on its handlebars/seat to remove the rear wheel to pack the coaster with grease, no fuel in the tank of course.
Re-torqued the head after the engine cooled. It had settled a bit. Its most important to do this.
Am going to experiment with filling the seat tube with silicone to try and remove the vibes from the seat. This is the smoothest CG I have owned and the vibes aren't a big deal. Just curious what a caulk gun tube of the stuff will do.
So, so far so good. We will see how long it lasts. I wonder.
 

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cannonball2

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Oct 28, 2010
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Colonial Coast USA.
Ordered the SBP sound deadening kit last night. Will see how well it works. If the noise is significantly reduced and the minor vibes can be eliminated from the seat post this would be a very nice ride, its still nice as is.
 

Ludwig II

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Jul 17, 2012
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I have to ask. Have you considered a strut from the middle of the seat post to the back of the frame on the chain side, and possibly a cross piece from under the engine to the lower tube?

Just as an experiment, you could try a piece of wood wedged in under the engine and see if it makes a difference.
 

cannonball2

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Oct 28, 2010
3,682
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Colonial Coast USA.
No L2 Havent thought of that. My past CGs vibed so badly that it was felt thru the pedals, seat and handle bars. Your hands and feet would tingle after a ride. That's the reason I bailed with these engines earlier.
This is a mild vibe just in the seat. Im pretty much convinced that filling the seat post and tube with silicone adhesive will cure the problem. Could be just a simple as changing to a larger seat. Just want to see if my theory is correct. By earlier standards this engine is light years smoother. Harmonics are a fickle thing. I had a early VW rabbit diesel that vibed the dash at idle. The crude but totally effective fix was two bricks siliconed to the inside of the front bumper. Maybe I need a bob weight attached to the seat.
 

cannonball2

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Oct 28, 2010
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Funny L2!
Rode a bit more today. Added a Stewart Warner NOS speedo I had a while. Its unusual in that the zero point is at the 11:00 position and it turns backwards requiring the drive to be mounted on the left. Seems very accurate. Now equipped with the speedo I can see that I don't want to take this assemblage of Chinese thinly cast, mismatched machining much higher than 25mph due to the noise factor alone. At idle the gear cover makes noise like its loose. Put your finger on it and its quiet. Thing is its not loose, just resonating. Thinking the SBP kit will help a lot.
The reed kit I am liking. Have read mixed reviews, but mostly from folks thinking its a performance mod when bolted on. Requires porting for that. For my low performance version it works well in the lower rpm ranges. The idle is very nice, especially for a non-broken in engine. There is plenty of low end I don't think would be there with it being just piston ported. That's what Im after low speed power. The sweet spot cruise is 22-25 mph(44t sprocket) very smooth(for a CG) there. Also like Running the BMX chain. They are pretty strong especially for a low out put cruiser. There are no clearance issues due to its narrow profile and I have yet to hear any chain noise(like I could over the castings). Despite the stone ax engineering Im liking this thing pretty good. If it becomes horribly problematic it will become a hanging in a friends bar. Will look pretty cool through the alcohol haze in the room Im sure.
 
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Ludwig II

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Jul 17, 2012
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It looks well enough as it is. The noisy casing, have you some sort of badge you could glue to it to look smart and kill some of the noise?
 

cannonball2

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Oct 28, 2010
3,682
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Colonial Coast USA.
It looks well enough as it is. The noisy casing, have you some sort of badge you could glue to it to look smart and kill some of the noise?
That's what the SBP deadening kit will do but from the inside of the covers. Plan on filling the seat tube and post with silicone adhesive today. We will see how that goes.
 

cannonball2

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Oct 28, 2010
3,682
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Colonial Coast USA.
OK filled the seat post and tube with silicone. Not a fun job! In order to force the silicone down the tube I had to make patches similar to a muzzle loader, rammed home by a long 3/8 extension. Also had to remove the bottom bracket and plug the tube from that end. After about half an hour, using an entire roll of paper towels and all the profanity I have accumulated over the years the job was done. I have high hopes this will work. I have used silicone as vibration isolation for years. With my luck though it will probably redirect the vibes to an even less desirable location. We will see
The engine has two tanks through it(close to a gallon I guess) with the 20:1 30wt mix. I had wanted to replace the inferior looking base gasket with a better one so pulled the jug to do so. I found the engine very well oiled and the bore beginning to break in nicely. Will switch up to synthetic 2 stroke oil@ 25:1 for the next gallon. Will ultimately settle on a 2stroke oil mix@ 40:1. I would really like to see one of these engines cast from a decent aluminum alloy! This is the most brittle stuff I have worked with!
 

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Ludwig II

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Jul 17, 2012
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It will eventually go off, probably in 3 years time.

As for brittle castings, well, even back then corners were being cut; there's no point in using a different metal to stand automotive use when it's only got to sit there day after day.
 

cannonball2

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Oct 28, 2010
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Probably faster than you think. Its open on both ends. Even capped my caulk tubes harden relatively fast. Humidity causes curing and we got plenty of that! Rode it a bit and cured or not it has eliminated the vibes in the seat and pedals. The bars have a bit but I just got through shooting them full of Great Stuff foam. Used a trick I should have used on the silicone. Bought some cheap 3/8 vinyl tubing. Shoved it through the bars until it was about 3" from the other side. Shot the foam to it and slowly with drew it to the side I started on, filling the bars completely. Will let it cure overnight and see how it works.

Found the carb leaning on extend high end runs. Discovered almost no fuel in the bowl due to the extreme angle. Ran fine if you were not too far into the throttle. So I carefully sawed the spigot off the RSE carb plate, planed it flat and bolted the stock manifold over the modded plate. Problem solved. I also added ATV chain tensioners to the rear wheel. Seems like no matter how hard you tighten the axle nuts the wheels walks from pedal starting. Also a pic of the SW speedo.
 

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Ludwig II

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The silicone trick is one I'll remember. £1 a cartridge over the road. I have to see how my two builds affect the back wheel, I might need adjusters as well.
 

cannonball2

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Oct 28, 2010
3,682
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Colonial Coast USA.
Been having a spell of rainy weather so haven't done any riding until it cleared a bit today.
The silicone and foam in the handle bars have turned this into a fairly civilized ride vibe wise. This engine is pretty smooth any way though. I knew vibes would show up some where else though, the formally smooth speedo now vibes a bit. Its mounted on the stem just before the dampened handlebars. Need a damper for it now. The SBP dampening kit works fairly well. Its worth the money. Reduced the engine mechanical noise by probably 25-30% Im guessing.
I switched from a slant fire head to a straight fire and in my opinion the engine runs better. Seems smoother, its lower compression. My thinking behind this CG experiment is to run the engine stock with the only improvements being for longevity/reliability/runability. Ordered a cheapy "expansion chamber", not much in the way of a performance type, but certainly better than the stock muffler.
The outset of this thinking is that the engine is easily replaced/repaired by another out of the box unit or stock parts.
I believe this engine will get a solid useable 30mph, which is plenty fast for this frame.