Kymco K-Pipe

I cut the mounting posts down with a standard pipe cutter but anything would do, they're "steel" but not much stronger than the pot metal variety.

Honestly, nothing, the motor is so choked up with the little carb it just can't make enough power to get past around 60mph on flat ground. Downhill I saw 70 with the original gearing but that was an outlier ( on the blueridge parkway, downhill, full tuck).

I'm definitely planning on carb and cam next, I think there's a little more to be had from this motor.

Gotcha.. I'm planning on going up a tooth on my 250 hoping to pick up 3 to 5 mph across the board but primarily concerned with middle cruise.
I'm looking forward to updates on the engine.
Don

I was up to something yesterday,

results will be discussed soon.

Ok. So what are you up to ?

So, my wife was out of town for a few weeks and I decided this would be the best time for me to undertake some K-pipe related projects.

This is where I left off last time...


After confirming a few measurements with another K-pipe owner, I decided to take a risk and order a cam that in theory should fit... http://dratv.com/stli15ca.html


This is a cam out of the lifan 150, It has about the same specs as one of DRATV's performance cams but also has the Decomp thingy still on it for easy kickin.

Install was extremely straight forward, the horizontal engines are some of the easiest to disassemble and modify, between beers this took under an hour.

Oh, and what led me to the cam swap was something I had done the previous week that didn't yield the performance enhancement I was looking for, I installed a knock off Mik-china carb and intake.


And in the process removed a lot of emissions crap that wouldn't work without the stock intake and air box.



So here's my take on these to mods as I let my morning coffee settle in:

1. Carb and Intake. This one was a mixed bag. Upon comparing the aftermarket components to the stock choker, you would think this would unleash the Beast! The stock intake chokes down to a few millimeters smaller that the head and has a very restrictive bend right after the carb, which is also a tiny little choker of a thing. Enter the Mik-china carb, the intake ID matches the carb and the head, has a much less acute radius and the new carb has a much bigger hole in it! Sounds great! But in the end it was only part of the solution. After installing this on an other wise stock motor and getting it tuned in I only saw a very modest bump in performance in the mid range and a very annoying bump in induction noise. It seems something else was choking it up, enter the...

2. Cam. This was a gamble, there isn't much info on the K-pipe motor beyond it being some variant of a horizontal clone, which there are many. Thankfully everything fit up just fine and I now suspect this is a rebadged Lifan motor. Anyway, this is what this bike should have had from the factory. This made the carb totally worth while, the bike has more power all over the place, especially in the mid range and up top. It revs out cleanly to "redline" and idles perfectly. instead of feeling like I'm always banging around gears to wheeze out of corners, I can just roll on the throttle. The bump in mid range punch has really made this a much more pleasant bike.

Now, do I recommend these two very cheap mods? Yes, but if I did it again I'd go for a real Mikuni, the knock off has been very fiddly.

Did this unleash earth shattering performance? No, but it did make an extremely anemic bike much more rideable and a lot more fun under 45mph.

So that's my morning coffee take on messing with the K-pipe.

Wife Approved and that's all that really matters.

That’s awesome. Thanks for the update.

For around $80 I think these two mods are totally worth doing (I've spent far more on far less) as long as you're ok with the induction noises.

It does sound much better after the cam, less bubble machine, more dirt bike.

Okay, so I recently pulled the trigger on 2 (that's right...2) Kymco K-Pipes. One had some bodywork damage but was mechanically sound, the other was like-new but with more than 2000 miles on the odo. So far, I've turned 1 into a cafe racer (see pics). Have not yet begun to work on number 2.

Can't wait to see what you come up with. It's nice to have multiples of the same bike.

Hope to pick up a 2018 K-pipe with 300 miles on it for $1800 tomorrow. I'm not a motorcycle guru so need to ask, is it possible to put smaller and maybe dual sport wheels and tires on this bike. I'm 5'4" and although I will probably be able to touch the ground I think it would be more comfortable to be an inch closure. I also plan on having it on the back of my RV and would like a small bike that could easily handle dirt road or slightly off the path riding once in a while.

Not sure about the wheels and tires, I find the stock setup does just fine in anything but mud.

As for the price, I suggest you look at cycle trader for new old stock. I picked up a 2017 brand new for $1k before fees and I see there are still some on there for $1299.

I purchased mine from Hall's Motorsports, they were willing to send it to whatever dealer was closest to me in their network. I also think they'd be willing to negotiate a little on price considering these bikes are old stock.

Of course that all depends on your location, good luck and welcome to pipe-life!

Hey, thanks for the reply and the welcome.

Yeah, I have been looking for quite some time on Cycle Trader, Facebook, Craigslist, etc. and unfortunately in Colorado they are hard to find. Looks like the closest Hall's is 1000 miles from me, and the closest one from a different seller is over 600 miles away, There are no other dealers in Colorado that I could find that have any of them, new or old right now. I ended getting it for $1600 which with the low miles and the fact it was only 70 miles from me, I can live with.

The wheel/tire change question was mostly if I can put slightly smaller wheels/tires on it, just to get my feet down a bit more comfortably, doesn't necessarily need to be knobbies or 50/50 tires, just figured if I was gonna get smaller tires, that would be the time to change them to be more versatile.

Can I get the specifics on those tires? Thanks!

I am going to take a guess and say they are IRC GP-1 dual sport tube type tires. I bet the front is a 3.0-17 and the rear is a 3.5-17. I am thinking about getting these tires for mine and just sucking it up and running tubes in them. I just finished building another 250 dual sport so while I don't need a bit more aggressive tire for my K-pipe I do like the look, and its nice when I explore down dirt roads.

For those interested in doing the stage 1 engine performance bump inmate downtavern did on his, you might also consider intake tuning, could be as simple as adding a length of radiator "L" hose between the carb and airfilter. Making a custom one with a reverse cones at either end is closer to the original Honda tuned intake tracts used on their iron head OHV 50cc and 90cc bikes.

These little singles benefit from having a bit of carb/airfilter separation, and consistently sized tube length between the carb's throat and the air-cleaner. It pushes the power band up a couple thousand and allows the engine to rev more freely throughout the entire RPM range.

I totally agree and see merit in pursuing this when time allows. I've had two of the iron head hondas and can attest to the surprisingly usable powerband. I currently have a ca110 Sport 50 in pieces awaiting a full rebuild, it has a beautiful 20ish? Inch air horn built in to the sheet metal frame.