250cc OHC Air Cooled rebuild Issues!

[Weldangrind]

Originally Posted by JohnWayne007

i also never thought of switching the transmission to an xr200. thats actually a good idea, i may have to look further into that. might just be my next project

I haven't tried physically fitting the transmission yet, but I think it will also drop in a CG.

[Weldangrind]

Originally Posted by humanbeing

To whom needs OHC 223 parts ,the alternative (ie. needs agent)
As stock
http://item.taobao.com/item.htm?id=35517374143
Higher grade:
http://item.taobao.com/item.htm?id=17587251271

Thanks for the links, HB. I might just buy a CB223 upgrade kit that has everything.

[JohnWayne007]

Originally Posted by Weldangrind

Maybe it needs a fatter slow jet. Have you tried crutching it by backing off the pilot mixture screw a little more?

When you say the clip is in the fourth groove, is that from the top or bottom?

I suppose i should have made that a little more clear, when i said the 4th groove lol i mean that i richened it by moving the clip to the 4th groove kind of like this...

Lean -1st groove
-2nd groove
-3rd stock groove
-4th groove (current position)
Rich -5th groove

so the 4th coming from the top down. it may need a fatter slow jet i haven't really thought much about that and i turned the fuel screw out more but it seems like the further i turn it out the worse it gets or starts to smoke, for some reason it really likes the position its at right now other than it imitating pop corn i did install a copper exhaust gasket recently a buddy of mine pointed out that the gasket might be my problem since it never use to have one. this popping noise comes from the tip of my muffler. its actually pretty weird, other than that noise the bikes overall sound is good, really "snappy" and runs way better than it did before.

Also my soft spot for CG engines is pretty big mostly because they are super easy to fix when there is a problem, my buddy i refer too has a 250cc CG air cooled and we did a big bore kit on his and it runs like a dream. i have a very good place here in Canada that i can get pretty much every part for a CG engine for a really decent price i keep bugging them to start Carrying CB parts but so far no luck

[Weldangrind]

Originally Posted by JohnWayne007

I suppose i should have made that a little more clear, when i said the 4th groove lol i mean that i richened it by moving the clip to the 4th groove kind of like this...

Lean -1st groove
-2nd groove
-3rd stock groove
-4th groove (current position)
Rich -5th groove

so the 4th coming from the top down. it may need a fatter slow jet i haven't really thought much about that and i turned the fuel screw out more but it seems like the further i turn it out the worse it gets or starts to smoke, for some reason it really likes the position its at right now other than it imitating pop corn i did install a copper exhaust gasket recently a buddy of mine pointed out that the gasket might be my problem since it never use to have one. this popping noise comes from the tip of my muffler. its actually pretty weird, other than that noise the bikes overall sound is good, really "snappy" and runs way better than it did before.

Also my soft spot for CG engines is pretty big mostly because they are super easy to fix when there is a problem, my buddy i refer too has a 250cc CG air cooled and we did a big bore kit on his and it runs like a dream. i have a very good place here in Canada that i can get pretty much every part for a CG engine for a really decent price i keep bugging them to start Carrying CB parts but so far no luck

Thanks for the explanation; did you try the fifth groove? Is the popping consistent across the entire RPM range or only at idle / off-idle? What jet sizes are you running now?

What size was the air cooled CG punched out to?

Who is selling CG parts in Canada?

[JohnWayne007]

Originally Posted by Weldangrind

Thanks for the explanation; did you try the fifth groove? Is the popping consistent across the entire RPM range or only at idle / off-idle? What jet sizes are you running now?

What size was the air cooled CG punched out to?

Who is selling CG parts in Canada?

it happens consistent across the entire RPM range and i have not yet tried the fith groove

Needle jet is 30
Main Jet is 105
and slow jet is 36

i get most of my CG parts from http://www.scoot-tuning.com/CG-engin...0cc-s/3465.htm

and i had changed his from a 67mm bore to a 70mm bore, usually if they dont have somthing on the site that you need all you have to do is contact them and chances are they have it just not posted yet. great company

[Weldangrind]

You must be using a Keihin for the slow jet to be that large; a Mikuni would be closer to 25. I'd step up the main jet to 110. I have some extra Keihin jets and emulsion tubes if you want them. Just PM me your mailing address. I can even drill them to whatever size you like.

You might also need to step up to 38-40 for the slow jet.

Thanks for the link. I presume you're having parts shipped from QC; how are the shipping costs?

Did you need to open the mouth of the bottom end, to accommodate the 70mm bore cylinder, or did you simply bore out the original cylinder?

[JohnWayne007]

Originally Posted by Weldangrind

You must be using a Keihin for the slow jet to be that large; a Mikuni would be closer to 25. I'd step up the main jet to 110. I have some extra Keihin jets and emulsion tubes if you want them. Just PM me your mailing address. I can even drill them to whatever size you like.

You might also need to step up to 38-40 for the slow jet.

Thanks for the link. I presume you're having parts shipped from QC; how are the shipping costs?

Did you need to open the mouth of the bottom end, to accommodate the 70mm bore cylinder, or did you simply bore out the original cylinder?

PM Sent, thank you by the way! and your welcome for the link, i have another somewhere if i can find it ill send it your way. and surprisingly i dident have to open up the mouth of the bottom end i figured we would have had to do a little bit of modding to get it to fit but once the kit came everything slid right together. i had purchased the whole kit, Cylinder/Piston/Rings/ Valves/ and it even came with a complete gasket kit for the whole engine . Now for the shipping cost it was actually pretty good, i think i only paid $200 all together shipping included if i remember correctly

[JohnWayne007]

Here is the other link http://www.chinese-parts-canada.com if you go to Cylinder Kits and Big Bore Kits at the bottom there is a request form if you cant find what you are looking for on their site, they have a distributor in Canada witch is the first link i sent you, so if you cant find what you are looking for on the first link try that one and send a request, they make a lot of changes so sometimes things wont be available through the site and only through request and vise versa

[Weldangrind]

Thanks again. Since I'm not in a hurry, I'll continue to order through Taobao. If I ever need something quickly, I'll be sure to try the links you shared.

[JohnWayne007]

Originally Posted by Weldangrind

Thanks again. Since I'm not in a hurry, I'll continue to order through Taobao. If I ever need something quickly, I'll be sure to try the links you shared.

No problem at all! most of the time when i need to order something it ends up being something i need in a hurry so i find it good to have local places i can order from. Another good site is www.multinationalparts.com they are great and shipping is awesome, right to the door!

[Weldangrind]

Originally Posted by JohnWayne007

...surprisingly i dident have to open up the mouth of the bottom end i figured we would have had to do a little bit of modding to get it to fit but once the kit came everything slid right together. i had purchased the whole kit, Cylinder/Piston/Rings/ Valves/ and it even came with a complete gasket kit for the whole engine .

I forgot to comment on this. Did you happen to compare the cylinder wall thickness of the original cylinder to the new one? What was the bore and stroke before? What is it now?

[JohnWayne007]

Originally Posted by Weldangrind

I forgot to comment on this. Did you happen to compare the cylinder wall thickness of the original cylinder to the new one? What was the bore and stroke before? What is it now?

if i can remember correctly the original bore and stroke before was 67x65mm and was changed to 70mm, i think that the cylinder was the same as the original just bored out to 70mm, i could have just bored out the original cylinder but it would have had to been re sleeved due to it pretty much blowing up, he had taken it out for a ride and heard a big bang and the bike completely stopped, he ended up pushing it home. i tore into it and the piston was toast, cylinder walls were beyond repair and piston rings were melted into the piston. so i ordered the big bore kit and didn't think to take measurements, i will be splitting the case in the near future just to check the internal components and clean it up a bit, he wants the engine re painted so i will probably take it all apart sand blast it and give it a new finish so when i do i will be sure to take as many measurements as i can and post them for future references, i actually still have the old cylinder and piston laying around to compare the big bore kit too once i do.

[humanbeing]

Originally Posted by Weldangrind

...Since I'm not in a hurry, I'll continue to order through Taobao...

Wholesaler from http://www.gzbymarket.com
usually had the best price
1 of them http://shop106450385.taobao.com that describe clearly from which maker

[Weldangrind]

Originally Posted by JohnWayne007

if i can remember correctly the original bore and stroke before was 67x65mm and was changed to 70mm, i think that the cylinder was the same as the original just bored out to 70mm, i could have just bored out the original cylinder but it would have had to been re sleeved due to it pretty much blowing up, he had taken it out for a ride and heard a big bang and the bike completely stopped, he ended up pushing it home. i tore into it and the piston was toast, cylinder walls were beyond repair and piston rings were melted into the piston. so i ordered the big bore kit and didn't think to take measurements, i will be splitting the case in the near future just to check the internal components and clean it up a bit, he wants the engine re painted so i will probably take it all apart sand blast it and give it a new finish so when i do i will be sure to take as many measurements as i can and post them for future references, i actually still have the old cylinder and piston laying around to compare the big bore kit too once i do.

A 70mm bore and 65mm stroke becomes an honest 250cc, without rounding up (like most manufacturers do). I might grab a kit like that for a project I have in mind.

Please start a thread on your friend's CG, when you blow it apart for paint.

[Weldangrind]

Originally Posted by humanbeing

1 of them http://shop106450385.taobao.com that describe clearly from which maker

Thanks, HB. Have you seen a 70mm cylinder kit for an air-cooled CG?