CG250 Performance Cam Installation.

[Megadan]

I will try to keep this as short as possible, especially considering many of you have probably read my main build thread, so for the sake of non-repeat I will be brief.

As many of you know the CG250 is a venerable bulletproof motor that makes great grunt power in the low and mid range, but lacks a bit of "go" and becomes short of breath once you ask it to do anything over 7000RPM.

In my quest to improve the performance of said motor, like a few others here, I ported my head, added a bigger carburetor, done all of the typical mods, and while they all made the bike very strong, it still suffers from that anemic top end.

The only solution to get a highway capable bike was to gear up almost to the point of being impractical for off road use, which does defeat the purpose of having a dual sport motorcycle. So began my search to stretch the top end, which eventually lead me to the WGK Camshaft being installed in the video below.

One thing I think that some people are mistaken about is how I am trying to build this motor. I don't want a race engine. I want a powerful but balanced street and trail capable engine with a solid power curve.

For details on the cam and how to order one for yourself, I will provide a link to my post on that exact information here: http://www.chinariders.net/showpost....&postcount=221


As for the video, I have finally reached the subscriber count to be able to monetize my videos, so I have done so. My main goal is to hopefully make a little extra money in order to help buy some better recording and editing equipment and software so I can in turn make better videos in the future. I doubt I will make very much, but hey, it's worth a try. Who knows, maybe I can even wrangle another bike to work on out of it too.

Also, be warned, this is a 47 minute video, and that is after I intentionally tried to make it short. There will be a second part for the riding an impressions here soon.

[JerryHawk250]

Sound great!

[Megadan]

Originally Posted by JerryHawk250

Sound great!

I want to ride it so bad! Both of us have been stopped by the fun police weather gods.

[JerryHawk250]

Originally Posted by Megadan

I want to ride it so bad! Both of us have been stopped by the fun police weather gods.

It looks like Thursday will be decent to take her to work. I'll pack the rain gear just in case. I'm not scared. Well maybe a little. lol

[China Rider 27]

Does sound good and strong! Looking forward to the riding evaluation. Couple things I am wondering about. 1) Could the cam be installed without removing the cylinder 2) Could not a guy use a vise with some wood to press that cam on and off similar to a knuckle on a u joint.

Excellent instructional video and is what is needed so the average guy can feel confident in taking it on. I would make the suggestion for the lighting consider the use of a headlamp. I will sometimes tilt my head around the camera when I have the shot lined up to focus the light spot where I need it.

The bar has been raised! CG strong, ride hard!

[Megadan]

Originally Posted by China Rider 27

Does sound good and strong! Looking forward to the riding evaluation. Couple things I am wondering about. 1) Could the cam be installed without removing the cylinder 2) Could not a guy use a vise with some wood to press that cam on and off similar to a knuckle on a u joint.

Excellent instructional video and is what is needed so the average guy can feel confident in taking it on. I would make the suggestion for the lighting consider the use of a headlamp. I will sometimes tilt my head around the camera when I have the shot lined up to focus the light spot where I need it.

The bar has been raised! CG strong, ride hard!

1, No, the cam cannot be installed without removing the cylinder and flywheel, Fortunately, that really isn't such a bad thing as it is only a couple more steps after removing the head for the cylinder to then come off.

2. You could possibly use a Vice to press the cam out. It will need to be able to press through all the way, so a socket just a bit smaller than the hole on one side and a pair of blocks onthe other with a bit of gusto could do it I bet. A Ball Joint installation tool with a large enough cup on the other side could also likely get it with some creativity. I have a cheap Harbor Freight 12 ton press and it barely took any effort. I bought it for stuff just like that when working on projects.|

The problem with the headlamp idea is that my camera was on my head for some of that lol. I just need to go get one of those LED shop lights to hang over the table. I was thinking about a chest camera mount though, since I am so tall all of the angles were a bit off. That might work with a headlamp.

[2LZ]

With all due respect Dan, I don't care much about your channel, making $$ off it, or even a 47 minute video or buying new equipment. I just want to know how camming a ported head CG motor sounds and runs!
We are the China Riders. We are a community of cheap-ass bike riders. Guess I'm just old fashioned.

[Megadan]

Originally Posted by 2LZ

With all due respect Dan, I don't care much about your channel, making $$ off it, or even a 47 minute video or buying new equipment. I just want to know how camming a ported head CG motor sounds and runs!
We are the China Riders. We are a community of cheap-ass bike riders. Guess I'm just old fashioned.

lol. Trust me, I will get to that as soon as possible. That's all I really care about at the end either. I just know that some people might complain about the ads, hence the disclaimer.

[bogieboy]

dan, any reason why you did a piston and jug along with the cam? how much is the cam itself, i see that the whole setup was about $95 or so... which isnt bad at all...

[Megadan]

Originally Posted by bogieboy

dan, any reason why you did a piston and jug along with the cam? how much is the cam itself, i see that the whole setup was about $95 or so... which isnt bad at all...

Must not have watched the part toward the reassembly side of things where I said I wasn't using the new cylinder. I had a new cylinder and piston on hand because I was unsure of how my rings and cylinder would look during disassembly and I am a total Boy Scout.

I may be obsessive about maintenance, but I was also a bit hard on this motor early in its life. Setting up two different carbs, and thrashing on it on the highway. I didn't want to discover deep scoring or some other sort of damage and not be prepared for it. Thankfully it just had light superficial skirt wear, no score marks in the cylinder beyond the matching skirt scuffing, of which the cross hatching was still visible through, and according to my bore gauge it was still round.

That's fine by me, because I have some ideas in my head as to what I can do with that cylinder, piston, and the old Hawk head for a different high compression ported setup. I am actually going to start on that head here shortly just as something to do on the side.

[bogieboy]

i admit, i only watched the startup portion of the vid....LOL its amazing how much abuse these motors can take, yet come out unscathed. my Shinray came to me with the rings STUCK in the piston, like, i still have the sucker 7 years later and half the ring is still in it...LOL and i slapped a new piston in after a light hone and it runs great.... as long as the motor has any oil, it usually turns out ok.... LOL

[ChipToothy]

I watched the vid and am impressed. Way cool! I already have 12,000+ miles on my motor so it’s a lost cause but I did enjoy the breakdown and explanations. These motors are a lot more complicated on the inside than what I was picturing. Thanks for sharing.

[ChipToothy]

I noticed you MegaDan have a brake light fix too? Mine hasn’t worked in a year for the rear lol and now I have a whole new everything rear brake wise it would be nice to have a rear brake light again.

What product-method is the easiest to make work?

[Megadan]

No ring compressor is needed as the others stated. The bottom of the bore is tapered, so just make sure its oily and it will go right in with a bit of care.

Originally Posted by ChipToothy

I noticed you MegaDan have a brake light fix too? Mine hasn’t worked in a year for the rear lol and now I have a whole new everything rear brake wise it would be nice to have a rear brake light again.

What product-method is the easiest to make work?

Goodrich banjo bolt brake switch.

[Megadan]

So the damn rain FINALLY stopped (3 days straight, I am not kidding) so I got to take the bike out for a proper first ride...

EDITED:

So, as it sits on my first impressions, and bear in mind I am still working out the changes to my fueling, definite boost in power, and a slight shift in the power curve, but only just a slight one. I think that just comes down to the nature of the CG250. Even with wonky fueling this thing felt way stronger than it did before the cam. Engine Revs up so much faster, and acceleration just feels much more effortless.

My fueling is all wonky though, as I mentioned before. At first I thought I had lean issues, but after some tinkering I believe I have it figured out now.

As I started the carb has a 35 pilot, 140 main. Idle mixture about 1 3/4=1 7/8, needle in the 3rd slot.

I thought I was having some lean issues at the transition from the pilot to needle, and also rolling out of the throttle from the main. Turns out i had that backwards. Needle was actually just a tiny bit rich in the third slot. I discovered that after moving it to the 4th and started having actual bog issues instead of just slight hiccups.

Other issue at the same time was getting fast idles like my idle mixture was leanm when I went to tweak it it would then drop and almost stall if I tried to adjust the mixture or idle speed more than a little bit. That issue went away and my idle went dead stable with the needle moved up. Basically the rich needle setting was allowing enough fuel to mask my lean idle.

It started raining again, so I can't test my changes. I have the needle set in the second slot and I went back to the 38 pilot jet.

As far as I can tell, the 140 main is pretty close, if not entirely perfect. I do believe it is still a bit lean up top, but I am going to wait until I can determine the effects of the larger pilot and leaner needle. I do have a feeling that I may need to go up to a 145, but we shall see when I get there.