Light mods for the Coleman CT200U-EX
- Thread starter MJL
- Start date
I have basically the same minor mods - Header w. hotdog muffler, and K&N style intake, TAV + 60 tooth rear.
With a .036 jet and a new emulsion tube, it runs pretty good and has good power for a used engine, and starts first pull - I also have one of those surface gap Autolite plugs in it, but that may or may not make any difference.
This is the jet kit - I put the E-tube and the .036 jet in it :
https://www.amazon.com/gp/product/B08S7L3HK9/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
With a .036 jet and a new emulsion tube, it runs pretty good and has good power for a used engine, and starts first pull - I also have one of those surface gap Autolite plugs in it, but that may or may not make any difference.
This is the jet kit - I put the E-tube and the .036 jet in it :
https://www.amazon.com/gp/product/B08S7L3HK9/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
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You can get a non-EPA adjustable carb for the motor for $15-$20 :
https://www.amazon.com/Carburetor-Gaskets-Powersports-Hammerhead-Generator/dp/B07L4GL664
You don't have to get that exact one, find one cheaper - The market is flooded with them - They're everywhere :~)
Buy an adjustable carb, put the jets in that one, and then swap it onto your engine - That way, you don't need to mess with the stock one.
https://www.amazon.com/Carburetor-Gaskets-Powersports-Hammerhead-Generator/dp/B07L4GL664
You don't have to get that exact one, find one cheaper - The market is flooded with them - They're everywhere :~)
Buy an adjustable carb, put the jets in that one, and then swap it onto your engine - That way, you don't need to mess with the stock one.
If I needed a carb for my stock bike I would get this one. Read the product description and reviews.
DJ-1225R Carburetor, Stock RuiXing - ARC Racing
DJ-1225R Carburetor, Stock RuiXing - ARC Racing
Ok so this might be a dumb question, I think I know the answer. I cut a hole into my factory air box. Front and back. I have a TAV and straight pipe. I ordered the jets. I’m noticing it’s running it kinda stumbles now and doesn’t like full throttle as much. Is it running too lean now, because I’ve let it breathe without enough fuel? Will the jet fix this?. I was just gonna order a stage one kit, but I’ve been doin a little bit at a time. I kinda doubted how much a pretty k$n style air intake would be different results than my modified factory one. I’m new so I’m learning this is my first
Minibike / small engine I’ve messed with, but I love it, I’m learning very little goes a long way with these things so far
Minibike / small engine I’ve messed with, but I love it, I’m learning very little goes a long way with these things so far
Yes - Probably running a bit lean now.
I don't really think the K&N filter adds much, if anything, over what you've done - I bought it because I wanted to leave the stock set up intact, so I could go back, if my mods didn't work - Some of my ideas turn out that way (not working), and I like to have a fall back option ;~)
I don't really think the K&N filter adds much, if anything, over what you've done - I bought it because I wanted to leave the stock set up intact, so I could go back, if my mods didn't work - Some of my ideas turn out that way (not working), and I like to have a fall back option ;~)
OK, I don't know if there's a simple answer to this - If you had a really built engine, that developed lots of power at a high RPM, then the 60 tooth would let the engine breathe better, and you'd probably get a higher top speed.
OTOH, with a mild stage 1 motor, the 60 tooth would just give you more low end response, and probably take away a bit from the top speed.
If you have any hills to climb, or want more acceleration, you'd probably like it - If you just want speed on the flat, you probably will just run into the engine governor's top RPM limit sooner, and not like it. In other words, you'll have a lower top speed, but get there quicker.
I like my set up with the 60 tooth, as it has terrific power and acceleration, but I'm not interested in top speed, as I just ride off road.
Of course, you could just remove the governor, and then the 60 tooth would let you blow up the engine more easily
And, yes, you'll need a longer chain.
OTOH, with a mild stage 1 motor, the 60 tooth would just give you more low end response, and probably take away a bit from the top speed.
If you have any hills to climb, or want more acceleration, you'd probably like it - If you just want speed on the flat, you probably will just run into the engine governor's top RPM limit sooner, and not like it. In other words, you'll have a lower top speed, but get there quicker.
I like my set up with the 60 tooth, as it has terrific power and acceleration, but I'm not interested in top speed, as I just ride off road.
Of course, you could just remove the governor, and then the 60 tooth would let you blow up the engine more easily
And, yes, you'll need a longer chain.
OK, I don't know if there's a simple answer to this - If you had a really built engine, that developed lots of power at a high RPM, then the 60 tooth would let the engine breathe better, and you'd probably get a higher top speed.
OTOH, with a mild stage 1 motor, the 60 tooth would just give you more low end response, and probably take away a bit from the top speed.
If you have any hills to climb, or want more acceleration, you'd probably like it - If you just want speed on the flat, you probably will just run into the engine governor's top RPM limit sooner, and not like it. In other words, you'll have a lower top speed, but get there quicker.
I like my set up with the 60 tooth, as it has terrific power and acceleration, but I'm not interested in top speed, as I just ride off road.
Of course, you could just remove the governor, and then the 60 tooth would let you blow up the engine more easily
And, yes, you'll need a longer chain.
OTOH, with a mild stage 1 motor, the 60 tooth would just give you more low end response, and probably take away a bit from the top speed.
If you have any hills to climb, or want more acceleration, you'd probably like it - If you just want speed on the flat, you probably will just run into the engine governor's top RPM limit sooner, and not like it. In other words, you'll have a lower top speed, but get there quicker.
I like my set up with the 60 tooth, as it has terrific power and acceleration, but I'm not interested in top speed, as I just ride off road.
Of course, you could just remove the governor, and then the 60 tooth would let you blow up the engine more easily
And, yes, you'll need a longer chain.
Use a 420 chain. I can't recall how many more links you'll need.
With a stage 1 kit which is a larger main jet, filter kit, and a header you should not lose top speed with 10/60 sprocket gearing. The engine will just top out at a higher RPM if the throttle screw is backed out. If you are doing off road riding you should be happy with the 60 tooth.
With a stage 1 kit which is a larger main jet, filter kit, and a header you should not lose top speed with 10/60 sprocket gearing. The engine will just top out at a higher RPM if the throttle screw is backed out. If you are doing off road riding you should be happy with the 60 tooth.
You're looking at a non-adjustable carb, and I don't know if there's a way to get the jet out - It's probably pressed or molded in.
No idle mixture screw, either, right? This is why a non-epa carb was suggested - You can actually tune them, where with the ones that come stock on new engines, you can't do much, if anything.
I just bought a new 223 for a different project, and it has a carb like that - sealed and non-adjustable.
No idle mixture screw, either, right? This is why a non-epa carb was suggested - You can actually tune them, where with the ones that come stock on new engines, you can't do much, if anything.
I just bought a new 223 for a different project, and it has a carb like that - sealed and non-adjustable.
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Some guys will do the work to get the jet out, while others hit the easy button and buy a new carb. I suspect that they are drilling the jet open larger then forcing a tool into it to unscrew it. If you try that make sure you don't drill in too far and ruin the e tube.
I don't think that the non adjustable idle is a big deal unless the RPM is too close to engaging the clutch. Other than starting engine warm up an idling engine is useless.
I don't think that the non adjustable idle is a big deal unless the RPM is too close to engaging the clutch. Other than starting engine warm up an idling engine is useless.
If I were you, I'd make it easy on myself, and just buy a new carb - It's cheap, it'll come with removable jets, an adjustable idle mix, and you can play around with tuning it to your heart's content.
As SAS289 implied, if you don't know what you're doing, you could easily just screw up the stock carb, trying to modify it.
I don't think it's worth wasting any time with it.
As SAS289 implied, if you don't know what you're doing, you could easily just screw up the stock carb, trying to modify it.
I don't think it's worth wasting any time with it.