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I'm still pretty new to the 2 stroke world and though I'm pretty familiar with 4 stroke airbox, exhaust mods and big bores kits, the whole head cutting, polishing and porting process is unfamiliar territory for me. 
My main goal is to boost low-mid range power as much as possible and I'm more than willing to sacrifice top end as I'm rarely above 2nd gear.   As I understand it, the head mods make the combustion process more efficient and the porting/polishing helps to adjust the power band. 
I spoke with an engine tuner who can do the work and has a similar riding style to mine, so I think I may schedule the work to be done soon.  I'll keep you all posted on the progress. 
 
If you really want to do that, read back a ways in this thread about my 28mm carb install. It almost turns your 200 into a trials bike. I ride in similar conditions to you, hardly ever go faster than 30 mph and usually a lot less. I love what the little carb has done to my bike, and getting double the gas mileage doesn't hurt either.
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5 hours ago, nobade said:
6 hours ago, daddister said:
I'm still pretty new to the 2 stroke world and though I'm pretty familiar with 4 stroke airbox, exhaust mods and big bores kits, the whole head cutting, polishing and porting process is unfamiliar territory for me. 
My main goal is to boost low-mid range power as much as possible and I'm more than willing to sacrifice top end as I'm rarely above 2nd gear.   As I understand it, the head mods make the combustion process more efficient and the porting/polishing helps to adjust the power band. 
I spoke with an engine tuner who can do the work and has a similar riding style to mine, so I think I may schedule the work to be done soon.  I'll keep you all posted on the progress. 
 

If you really want to do that, read back a ways in this thread about my 28mm carb install. It almost turns your 200 into a trials bike. I ride in similar conditions to you, hardly ever go faster than 30 mph and usually a lot less. I love what the little carb has done to my bike, and getting double the gas mileage doesn't hurt either.

Thanks for responding, nobade!  I did see your thread on the install and it has definitely been an option floating around in my head.  I've always had my jetting work done by someone else and went with the Lectron as a set-it-and-forget-it alternative.  From what I understand, the wrong jetting on a 2 stroke can cause some major damage.  My typical riding areas fluctuate from sea level to around 5,000 ft and usually within the 65-85 degree range.  I have a few questions on your install:

-Is your 28mm carb more or less sensitive to elevation/temperature than the stock carb? 

-Are you able to loft the front wheel with just throttle in first and second gear or do you still have to drop the clutch?

-Did you make any gearing changes?

-What's your top speed?  

Thanks again!

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45 minutes ago, daddister said:

Thanks for responding, nobade!  I did see your thread on the install and it has definitely been an option floating around in my head.  I've always had my jetting work done by someone else and went with the Lectron as a set-it-and-forget-it alternative.  From what I understand, the wrong jetting on a 2 stroke can cause some major damage.  My typical riding areas fluctuate from sea level to around 5,000 ft and usually within the 65-85 degree range.  I have a few questions on your install:

-Is your 28mm carb more or less sensitive to elevation/temperature than the stock carb? 

-Are you able to loft the front wheel with just throttle in first and second gear or do you still have to drop the clutch?

-Did you make any gearing changes?

-What's your top speed?  

Thanks again!

If you like your Lectron, I wonder if you'd get a similar result with a smaller Lectron?  I have a 30mm from my sons 100 that he doesn't like, and I feel stuck with it.  I have tried many times to sell it with no luck.  If you want to test the theory I'd make you a good deal on it, or Nobade, or anyone else.

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1 hour ago, daddister said:

Thanks for responding, nobade!  I did see your thread on the install and it has definitely been an option floating around in my head.  I've always had my jetting work done by someone else and went with the Lectron as a set-it-and-forget-it alternative.  From what I understand, the wrong jetting on a 2 stroke can cause some major damage.  My typical riding areas fluctuate from sea level to around 5,000 ft and usually within the 65-85 degree range.  I have a few questions on your install:

-Is your 28mm carb more or less sensitive to elevation/temperature than the stock carb? 

-Are you able to loft the front wheel with just throttle in first and second gear or do you still have to drop the clutch?

-Did you make any gearing changes?

-What's your top speed?  

Thanks again!

It does seem to be less sensitive to changes. It is also very much easier to jet. I fought with the stock PWK38 for quite a while, and never got it to work like I wanted. It was always great from mid to top, but never would give the instant response I was looking for on the bottom. As far as elevation changes, I haven't tested that much. I live at 5300 ft and ride up to about 8000 ft. It works just fine through that range, but I don't have any way to try it out much lower around here. Acceptable jetting also seems to be a lot easier to achieve. I ran it for some time with the needle on the 4th clip, and it gave just a little bit of rich stutter right off the bottom and a lot of spooge. Then I started leaning it out one clip position at a time on each ride. It kept running better, less spooge and better response. I have it on the top, leanest position now and it is easily able to cruise on pavement at a steady throttle opening with no breaking up, and response off road is instantaneous. I am going to go with the next step leaner needle to see how it works, but I am just about perfect now. The point is, if the OEM carb had been that far off it would have unrideable. This one was just mildly annoying, but still way better than I ever achieved with the stock carb.

It will power wheelie in the first four gears. In first and second it is instant - hit the throttle and it pops up. I very seldom clutch any more except for really extreme rock crawling and of course to get moving. Now the response is so clean I can much easier maintain traction using the trials tire on the rear, just dial in whatever power I want. But if I whack it open the tire immediately breaks loose. Sort of like riding an electric trials bike.

Gearing is 13-50. Pretty low, but this is a MXC so it has the SX transmission and not the XC trans with the super low first gear. Top speed is about 55 mph or so. It's still plenty fast for the woods, once it is up on the pipe you had better have it aimed in the right direction.

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53 minutes ago, poldies4 said:

If you like your Lectron, I wonder if you'd get a similar result with a smaller Lectron?  I have a 30mm from my sons 100 that he doesn't like, and I feel stuck with it.  I have tried many times to sell it with no luck.  If you want to test the theory I'd make you a good deal on it, or Nobade, or anyone else.

I also have wondered what a small Lectron would do on this bike. I was all set to buy a Lectron, but after talking to James Dean about his tests of little carbs on big engines, I thought I'd try the PWK28 since they can be had really cheaply on Ebay and since I have one on my KX100 I have lots of jets and stuff for them. If anybody tries it on their 200 I'd love to hear how it works given how well the normal Lectron improves the response.

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Can anyone help me with wiring up an LED light for my '98 MX/C? I'm planning to make it road legal and sometimes ride at night so I don't just want to duct tape a flashlight onto the front fender. 

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22 minutes ago, nobade said:

It does seem to be less sensitive to changes. It is also very much easier to jet. I fought with the stock PWK38 for quite a while, and never got it to work like I wanted. It was always great from mid to top, but never would give the instant response I was looking for on the bottom. As far as elevation changes, I haven't tested that much. I live at 5300 ft and ride up to about 8000 ft. It works just fine through that range, but I don't have any way to try it out much lower around here. Acceptable jetting also seems to be a lot easier to achieve. I ran it for some time with the needle on the 4th clip, and it gave just a little bit of rich stutter right off the bottom and a lot of spooge. Then I started leaning it out one clip position at a time on each ride. It kept running better, less spooge and better response. I have it on the top, leanest position now and it is easily able to cruise on pavement at a steady throttle opening with no breaking up, and response off road is instantaneous. I am going to go with the next step leaner needle to see how it works, but I am just about perfect now. The point is, if the OEM carb had been that far off it would have unrideable. This one was just mildly annoying, but still way better than I ever achieved with the stock carb.

It will power wheelie in the first four gears. In first and second it is instant - hit the throttle and it pops up. I very seldom clutch any more except for really extreme rock crawling and of course to get moving. Now the response is so clean I can much easier maintain traction using the trials tire on the rear, just dial in whatever power I want. But if I whack it open the tire immediately breaks loose. Sort of like riding an electric trials bike.

Gearing is 13-50. Pretty low, but this is a MXC so it has the SX transmission and not the XC trans with the super low first gear. Top speed is about 55 mph or so. It's still plenty fast for the woods, once it is up on the pipe you had better have it aimed in the right direction.

Thanks mucho for answering with such detail!  I really appreciate your input.  It sounds like giving the PWK28 coupled with my stock 14/48 gearing may be the perfect balance for gaining low-end, being able to whack the throttle to lift the front in 1st or 2nd, yet not be geared too low to be jumpy with every move of the throttle. 

So just to confirm, there weren't any head mods or polishing and porting done in conjunction with your carb mods and gearing changes?  

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Thanks mucho for answering with such detail!  I really appreciate your input.  It sounds like giving the PWK28 coupled with my stock 14/48 gearing may be the perfect balance for gaining low-end, being able to whack the throttle to lift the front in 1st or 2nd, yet not be geared too low to be jumpy with every move of the throttle. 



So just to confirm, there weren't any head mods or polishing and porting done in conjunction with your carb mods and gearing changes?  
No engine mods, just a Gnarly woods pipe.
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1 hour ago, poldies4 said:

If you like your Lectron, I wonder if you'd get a similar result with a smaller Lectron?  I have a 30mm from my sons 100 that he doesn't like, and I feel stuck with it.  I have tried many times to sell it with no luck.  If you want to test the theory I'd make you a good deal on it, or Nobade, or anyone else.

Thanks for the offer, Poldies!  I'm going to chat with my mechanic soon to get his 2 cents on it.  It's sounding like giving a cheapo PWK28 would be a good start. 

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On 9/20/2017 at 7:34 PM, madwheeliemcg said:

Hey all.

I have a '98 200MX/C and I love it. However, some improvements could be made. I am only 5' 5" so this bike is a bit tall for me, and when I stop on uneven ground (anywhere but my driveway) I can only get one foot down. I need two things; a new seat and suspension help. The stock seat feels like sitting on a board and it sucks when you go for long rides, so I want a nicer one that is comfortable and maybe puts me closer to the ground. And for suspension, how can I lower the back? The front forks are already all the way up in the triple clamps. Other than it being a little big I love everything about this bike. 

Thanks,

Connor

I cut the seat on my 02 mxc and although was lower, I hated it.

Can't remember if the 98 frame is similar, However I took an 04 subframe and stuck it on the 02 mxc, then got an 07 ktm hard parts low seat.

didnt measure the exact difference but it was so much nicer in height and feel. 

Also had to replaced the tank from an 07

 

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Thanks for the offer, Poldies!  I'm going to chat with my mechanic soon to get his 2 cents on it.  It's sounding like giving a cheapo PWK28 would be a good start. 
Remember you will need to get some adapter rings turned to make the little carb look like the big one. Epoxy them on and the rest is easy and straightforward. The KTM throttle cable even works.
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