my67xr
Miniriders Legend and Master Spanner Spinning Mode
can you get a close up of that pin, on a piece of white paper maybe ?
New member, fixing up a 125 Atomik
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my67xr
Miniriders Legend and Master Spanner Spinning Mode
i think i could be the pin that retains the clutch compression lever into the clutch cover, the diameter is about 3mm,
(it normally has a flat head like a nail that stops it going in too far),
you should be able to see it if you take the smaller round side cover of the clutch cover, that is where you adjust the clutch freeplay.
if it is, then the chrome arm would be able to be turned and pulled out of the clutch cover a bit (more than 2mm, possibly right out ? ),
part number #8 here (click on it to enlarge the pic)
or it could be part of the gear lever return spring, (maybe one leg has broken off ?),
but they are usually shiny, and are about 4mm diameter, part #7 here-
(it normally has a flat head like a nail that stops it going in too far),
you should be able to see it if you take the smaller round side cover of the clutch cover, that is where you adjust the clutch freeplay.
if it is, then the chrome arm would be able to be turned and pulled out of the clutch cover a bit (more than 2mm, possibly right out ? ),
part number #8 here (click on it to enlarge the pic)
or it could be part of the gear lever return spring, (maybe one leg has broken off ?),
but they are usually shiny, and are about 4mm diameter, part #7 here-
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Yeah I thought that it might have been that pin in the clutch lever but it looks like it's got a knob on the end. I was more thinking that it was one of those number 13 pins on the gear pic. I will double check the clutch pin when I get home. I have started it and it seemed to run alright so meh lol.
my67xr
Miniriders Legend and Master Spanner Spinning Mode
if you can measure up the pin size against a drill bit that might helpe.
i have a few of those engines in pieces, and might be able to work it out.
was it inside behind the small clutch adjustment cover ?
or actually inside the big outer clutch cover with the clutch, oil filter screen and kickstart gears etc ?
that oil filter screen with the hole through the middle,
someone has given it an oil change at some stage and stuck a screwdriver or similar up through the hole, and prodded around to see if the gauze mesh was a blockage i reckon.
i have a few of those engines in pieces, and might be able to work it out.
was it inside behind the small clutch adjustment cover ?
or actually inside the big outer clutch cover with the clutch, oil filter screen and kickstart gears etc ?
that oil filter screen with the hole through the middle,
someone has given it an oil change at some stage and stuck a screwdriver or similar up through the hole, and prodded around to see if the gauze mesh was a blockage i reckon.
not sure what you're talking about here lol! :/
anyway the pin is 16mm x 3mm and it has a flat on the side which goes from the end approx halfway down.
it was actually inside the big outer clutch cover. I'm fairly certain it's not the pin for the clutch arm as that has no lateral play that I can notice.
Wow so it's been a long time since I've posted on here, I haven't had much of a chance to do anything to the bike for a while but I recently actually took it to the track for the first time.
I've only got a small yard at home so I'd been riding it around a little and it was working just fine but at broardy it wouldn't open past half throttle, anyway I brought it home and was mucking around for ages with needle clip positions etc trying to get some improvement, absolutely nothing, not to mention the thing was leaking like a sieve.
The carb I have fitted is this one which is a genuine CV mikinu from a Yamaha FZR250.
It wasn't until I visited a FZR forum to see if there was anything I missed setting it up that I saw a pic of it mounted.
This is a downdraft carb, no wonder it wasn't working haha, that little line to the left of the fuel inlet is meant to be vertical, not horizontal. I'm amazed it ran at all!
Anyway I re-mounted it (at the expense of the battery holder, the bike doesn't have a battery at the moment anyway) and it now revs all the way but it sounds way too lean.
So the standard main jet in these is a 72.5. These were ganged in a group of 4 so this carb drove a 62.5cc pot but the FZR revved to 20k RPM. So I'm trying to figure out what would be a good starting point for a main jet for my stock 125cc lifan.
I'm planning on taking one of the other jets from the gang and drilling it out with a 1mm bit to give me a #100 just to see if it makes any difference, but before I order anything I'd like a rough estimate.
Thanks!
I've only got a small yard at home so I'd been riding it around a little and it was working just fine but at broardy it wouldn't open past half throttle, anyway I brought it home and was mucking around for ages with needle clip positions etc trying to get some improvement, absolutely nothing, not to mention the thing was leaking like a sieve.
The carb I have fitted is this one which is a genuine CV mikinu from a Yamaha FZR250.
It wasn't until I visited a FZR forum to see if there was anything I missed setting it up that I saw a pic of it mounted.
This is a downdraft carb, no wonder it wasn't working haha, that little line to the left of the fuel inlet is meant to be vertical, not horizontal. I'm amazed it ran at all!
Anyway I re-mounted it (at the expense of the battery holder, the bike doesn't have a battery at the moment anyway) and it now revs all the way but it sounds way too lean.
So the standard main jet in these is a 72.5. These were ganged in a group of 4 so this carb drove a 62.5cc pot but the FZR revved to 20k RPM. So I'm trying to figure out what would be a good starting point for a main jet for my stock 125cc lifan.
I'm planning on taking one of the other jets from the gang and drilling it out with a 1mm bit to give me a #100 just to see if it makes any difference, but before I order anything I'd like a rough estimate.
Thanks!
my67xr
Miniriders Legend and Master Spanner Spinning Mode
Check your float level too, use some clear tubing off the fuel bowl drain and run it up past the top of the carb
Open the drain screw and let the fuel run into the tubing.
Check the level against the line across the float bowl
What bore size is your CV ?
A Mikuni copy 22/26 use's around a 92 or a 95 main jet for a 125, so try drilling it to .9mm first
Open the drain screw and let the fuel run into the tubing.
Check the level against the line across the float bowl
What bore size is your CV ?
A Mikuni copy 22/26 use's around a 92 or a 95 main jet for a 125, so try drilling it to .9mm first
Throat size is 26mm, funny that's the picture that I saw which made me realize my mistake, yeah I haven't checked the float level yet (with it in the correct position, i did check it before lol).
I don't have a .9mm drill bit which is why I was going for the #100 to start with, I've got 4 jets to play around with so I guess if it's super rich at least I'll know that it's between 72.5 and 100...
So this kit Carb Main JET Chinese 125 150 GY6 Scooter CG125 CVK FOR Scooters Atvs 10pcs | eBay would be way too big for the application?
I don't have a .9mm drill bit which is why I was going for the #100 to start with, I've got 4 jets to play around with so I guess if it's super rich at least I'll know that it's between 72.5 and 100...
So this kit Carb Main JET Chinese 125 150 GY6 Scooter CG125 CVK FOR Scooters Atvs 10pcs | eBay would be way too big for the application?
my67xr
Miniriders Legend and Master Spanner Spinning Mode
DHZ our site sponsor has the Mikuni jet's for $5 ea.
Mikuni Carburetor Slow / Main Jets ? Buy Online Australia at DHZ
Here's a 92.5 mikuni jet for $6.50 delivered-
NEW Mikuni Carburetor Main JET Size 92 5 | eBay
Jaycar sell Micro drill set's .3mm - 1.6mm for about $12, but that's pretty much the price of a new jet not including buying a Pin Vise $13.50
You can get the 2 from ebay for under $12 inc delivery ex china too
Then you'll need a pin vise to hold it in.
Do you have a welding tip cleaner ? But it will be hard to keep it straight through the jet.
And angled or offset hole will affect the flow of the jet
A set of them usually cost's under $5
Mikuni Carburetor Slow / Main Jets ? Buy Online Australia at DHZ
Here's a 92.5 mikuni jet for $6.50 delivered-
NEW Mikuni Carburetor Main JET Size 92 5 | eBay
Jaycar sell Micro drill set's .3mm - 1.6mm for about $12, but that's pretty much the price of a new jet not including buying a Pin Vise $13.50
You can get the 2 from ebay for under $12 inc delivery ex china too
Then you'll need a pin vise to hold it in.
Do you have a welding tip cleaner ? But it will be hard to keep it straight through the jet.
And angled or offset hole will affect the flow of the jet
A set of them usually cost's under $5
