KymcoForum.com

People have been making fun of my non-techie nature for over a decade now.  I left one site because people became downright mean about it.  Ironically some of these same people now call seeking help with their builds.

I bought the K-Pipe because I'm more-or-less "stuck in the 70's" and miss the simplicity and ease of maintenance these bikes offered.  I bought a Grom and tried really hard to get my head around fuel injection, carrying the shop manual around with me everywhere I went to study but it just never clicked.

My Dad insisted I take a full year of typing in high school figuring if his motorcycle bum son couldn't do anything else he could get a job as a clerk.  I never dreamed this skill would be of value to run anything like a computer.  Regardless my computer skills are limited and I have no intention of learning anything more.  My memory bank is full of redundant information now and while I can tell you all about a particular bike from the 70's or how to set the timing on a bike with a breaker point ignition my lack of skill behind this monitor will probably remain this way.

No offense or anger here (yet)--I just want everyone to know that I'm old fashioned as I can be before people start saying things like "pics or it didn't happen."  I'll be happy to go to great lengths to describe something but for those who hate reading better be ready to ignore my lengthy posts.  If that's offensive to the majority I'll stop posting and depart.

After a hundred mile ride to lunch today I decided to try gearing the bike up one tooth in the front to see how it would react.  The motor seemed to be "busy" (turning too many RPM) at an indicated cruising speed of 48 MPH and I thought if it would pull one more tooth in the front perhaps it would not only make it feel less busy but also improve it's cruising speed.

I'd previously put an "O" ring chain on it in the stock length but unfortunately it's too short to accept another tooth .  Off to the shop and I bought a regular #428 chain to experiment with.  It took 108 links to mate a 15 tooth sprocket with the standard 36 tooth rear (stock is 106).

Wow!! It still never fails to amaze me how gearing affects how a bike runs.  The bike now goes faster in each gear before shifting and will cruise at an indicated 52-55 MPH (actual 49-52 MPH according to my GPS).  This is pretty much equal to the Lifan powered Passport I rode to the Smokies from Indy last summer that I was using as a standard.

I'm sure in hilly country I'll be shifting more and next weekend I'll make another run to the hills to see how it reacts.

If you don't have to have an "O" ring chain this is a cheap change with the chain around $20 and the sprocket about $7 on eBay.  As mentioned this is a #428 setup and the front shaft is the same style/size as the older Hondas with a 17mm shaft (the Lifans use a 20mm output shaft).

Now I've gotta buy another "O" ring chain.  At least I can run the first one on another step through project I'm building.

If you want your bike to feel less busy and have a higher and more comfortable cruising speed give this a shot.  I think you'll like it.


Temperatures today got up to around 80 and the bike seemed to be running a bit rich at about 1/8-1/4 throttle opening on the Mikuni I'm running.  First I stopped and removed the steel washer I'd put under the clip and up the road stopped again and removed the brass washer leaving only the nylon one.  Both helped so I stopped again and swapped the brass one for the nylon one which visually is slightly thinner and again got an improvement.  The next step will be to try dropping the needle one notch and then juggle the washers to see what works best.

Life is great sometimes and this was one of those exceptional days when my experiments went well.

Unfortunately there's only one adjustment on the K-Pipe's carburetor, the idle screw.  According to the shop manual I have it's supposed to be set at around 1600 RPM which is a bit high for my taste but that's what they call for.

You'll likely need an accurate inductive tachometer to know what kind of RPM the engine is turning.  Just for tuning purposes I added a $15 one-wire tach/hour meter and eventually I plan to remove it.  Installing it is a piece of cake--you just wrap the wire around the spark plug cable a few turns.

The cap covering the mixture screw can be easily removed (it's held on with a soft glue similar to Silicone Seal) but once off you won't be greeted with a normal slotted screw head.  Instead what you'll find is more akin to a 3/4 moon.  I was able to move mine with a small screwdriver and a pair of needle nose pliers.  A bit of carburetor cleaner will dissolve the remaining adhesive and once removed you can cut a small slot in it for a screwdriver.  I'd start about 1 1/2 turns out.

Other things to check might be the air cleaner to make sure it's not over oiled.  What Redk said is also true.  Gasoline is filthy nowadays but the K-Pipe does have a filter stock.

As mentioned on the "2016 K-Pipe Owner" thread on page 3 I replaced the stock carb and airbox with an inexpensive Mikuni carb and air cleaner from eBay.  Doing this will allow unlimited tuning ability as well as quick warm ups.  I can light mine up, ride it away and be able to turn off the "choke" (actually an enrichening circuit on the Mikuni) before I get a quarter of a mile away.  There might even be a performance increase but without a dyno or another K-Pipe to run it against it's hard for me to tell.

I do like the simplicity of the Mikuni carb and I've used it on several bikes with excellent results.  Several other buddies have the same carb on their step throughs and share the same sentiment.  Jetting is easy to obtain and without an air box it's extremely quick to access the carb for adjustment or maintenance.

Manufacturers do this to make people feel comfortable sitting on them in the showroom.  It allows more people to get their feet on the ground, a huge selling point.  Only a handful of people find these seats comfortable when actually riding them.  The rest of us end up sitting on our "privates".

Until the mid-to-late 50's bikes had tractor-style seats that actually fit the human arse.  Some marketing wizard decided that "racing style" seats resembling vinyl covered loafs of bread looked better and they became the standard.  These seats evolved into what we have on bikes today.

We've become slaves to fashion.

Just for fun I picked up a seat from an FXRP cop bike at a swap meet and rigged it up on my XR-650L.  It was light years better than the stock seat.  Ugly, yes but very functional and I couldn't see it when I was riding it.  I got this idea from an old duck I know in Florida who put an old leather cop bike seat on various bikes (among them a BMW G/S and a Suzuki DR-350SE) and I was amazed how comfortable it was.

Even one of those cheap solo seats with springs popular on bobbers would work better for most people than the stock seats on dually bikes.

I don't see things changing anytime in the near future and the folks at Sargents will continue to make a nice living making these seats passable for our use.

More fun with the 22mm Mikuni carb setup...

The carb manifold adapter arrived and at least by my eyes didn't look totally flat.  I bought a piece of #320 paper, taped a piece to a surface plate and using a figure-8 motion lapped the top of it flat.  The bottom that goes against the cylinder head uses an "O" ring to seal it.  A tiny bit of Permatex High Tack holds it in place nicely while the adapter is bolted in place.

It didn't come with the needed flathead 6mm x 1 bolts so a trip to the hardware store got me a pair of stainless socket headed bolts 16mm long.  The adapter wasn't countersunk well so another trip to Harbor Freight got me a  90 degree countersink (HF #61552, $1.99) and a few minutes of work on the drill press later the bolt heads were nice and flat in the adapter.  Note that metric flatheads are 90 degrees on the angled surface, not the 82 degrees of SAE bolts so be careful that you use the proper countersink for these bolts.

I had a gasket in my inventory and more High Tack painted on it and a couple of 6mm x 1 bolts with 8mm heads 16mm long bolted the manifold to the manifold adapter.  (I tried bolts with 10mm heads but it's difficult to get a wrench on them.)  I bolted it on so that the carb now points about 20 degrees to the left.  Now there's no worry of the fender hitting the air cleaner.  I used blue Loctite on the two bolts that hold the manifold to the manifold adapter since the assembly isn't supported any other way to insure it won't shake loose.

I got out the phony blinker/sidecover assembly and it will still fit even with the carb/air cleaner pointing to the left if you wanted to retain it.

I have a fruit can about 4" in diameter and I may experiment with drilling a hole in the chrome cover of the K & N filter and install a bolt in the center of it to bolt on the can for inclement weather.  I've used plastic Fast Orange hand cleaner cans for the same purpose in the past on my Lifan powered step-throughs so one of these might end up on it with a bunch of holes drilled in the bottom to insure the filter will get plenty of air.

When I can get someone to get a picture or three of this setup I'll post them.  For now here's a picture of the manifold adapter I used except mine was black.

I took the day off and did a 150 mile loop on the K-Pipe down to beautiful Brown County, IN where the roads are hilly and twisty.

The good?  87 miles per gallon even with the  Mikuni carb.  The best I ever got with this carb on the Lifan motors was 80.  Happiness.

The bad?  For one, the seat sucks.  The forward downhill slope has me sitting on my balls and I'm constantly standing up and rearranging everything.  While this seat might fit someone with a shorter inseam (mine's 32") even then the slope will have them constantly pushing backwards against the bars.  I think if I level the the seat about an inch or so this will fix the problem at the price of increasing the seat height.  I'm going to go find a stadium seat pad, cut it to fit and try that as a temporary measure.

I shouldn't call this a bad thing but the motor doesn't have the grunt of my Lifan motors.  Coming out of corners where I could just grab a handful and torque my way out this motor requires me to downshift.  Gearing between my Lifan/Passport and the K-Pipe are about the same if tire sizes are computed into the equation and right now I have the same intake manifold/carb/air cleaner on both so that leaves the fact that the K-Pipe is a full point down on compression as part of the problem.  Without measuring and comparing them I don't know for sure but I suspect there might be a difference in the cam as well.

Could the giant muffler be restricting it?  Maybe.  On the Lifan/Passport I'm running a CRF-70 pipe sans spark arrestor screen and it's got a bark to it that the K-Pipe doesn't have.  I'm hoping that the volume of the K-Pipe muffler makes up for the fact it's not as straight-through as the Honda muffler.  It's wonderfully quiet and doesn't offend anyone.

I may put the pit bike muffler back on, haul it down there and do a bit of testing to see if there's any difference.  The muffler might be more restrictive than I think.  I hate to have that loud thing on there and I don't think I could stand to ride it down there and back so trucking it is the only alternative.  More on this after I give it a try.

*Edit--I went ahead and did another test with the pit bike muffler.  I can see virtually no difference in performance.  It is very light compared to the stock muffler that weighs almost as much as Oprah.

In an experiment to try to eliminate a slight occasional hesitation when I first give it throttle I swapped the stock intake manifold to the same one I use on my Lifans.  I suspected that the tight bend at the top of the stock intake manifold might be the culprit and I was right.  The smooth 45 degree intake completely eliminated the problem.  Sweet!

Here's a combination manifold/carb/air cleaner on eBay from a U. S. vendor:  #282384496040

Using this setup rotates the carb to the right and might hit the stock body panels (the ones the phony blinkers are mounted in).  I've got mine off so I can't tell you if there's going to be interference or not.

When the manifold adapter arrives I'll experiment with it and put the manifold/carb in different positions and see which one works best.