KC's new 4-stroke Jackshaft base

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KCvale

KCvale

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Feb 28, 2010
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scratchbuilder said:
That is nice! Hey where can I get a pair of just those bent arm cranks??? I'm putting the 79 pred. on my box in front long cargo bike and sbp bb is not going to be wide enough. Thx.
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Actually SBP has 212mm wide crank axles now but those funky wide crank arms are from gasbike 4-stroke kits I had leftover.

If you want some 79cc/Q-matic build tips I documented mine here.
http://kcsbikes.com/topic.asp?TOPIC_ID=639

I am redesigning my mount again.
It's just too darn big for the job and didn't account for direct drives.

No biggie other than I have to make another trip to the metal shop but I simply need to work design as I go and I can't do that with poster board or thin sheet metal, it won't how the parts in place.

I figure I better get some engines in stock since they are not easy to find without going through gasbike.
Found a source in the states with over 3 dozen HS 142F-1G 49cc and HS 144-1G 53cc engines in stock.

I haven't seen a 144, and it's only 5cc larger but what the heck, for all I know 5cc might mean 5mph so worth checking out I guess, especially if they are the same price.

For those of you interest in this...

What would like to buy as a package?

Just a 10G..
Just a base..
10G and base..
Engine, 10G and Base..
A whole kit with everything?

Or just maybe just whatever I have piece-meal?

Thanks.
 
KCvale

KCvale

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Feb 28, 2010
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Velodrome said:
I have a motor with straight shaft. Will that work with your kit? I'd need everything else.
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Nope.
The long shaft engines are for transfer cases that try to put the clutch bell and drive pulley on the engine shaft.

The 10G has a separate dual bearing shaft in the case so the engine needs the short shaft with the cutch on it to isolate the two parts.
gasbike has them for $129.

I'd have to sell them for $150 + shipping so doubtful I will carry engines.
 
KCvale

KCvale

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Feb 28, 2010
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Haven't rode it yet, but this base design looks to be the functional base...

The engine has room to slide all the way forward and the 360 grip U-bolt clamp is still easy to get to.



It has side tabs to keep the flat part rigid yet bendable for tube angle.

If need be I'll supply a couple little drilled pieces and bolts to set the angle and keep the shape at the bends via the side tabs.



The front is the easy part and where extenders for wider frames will go.
The business end is the back end and transfer case mount.

The TC has new mount holes to lower the extra long output shaft closer to the base and below the oil filler.
Yes, it's a breeze to change the oil with a syringe with this design.



The back piece sports 2 360 grip U-bolts to mount it flat against the back side of the seat post.

This is what gives you that 3rd strategic mount so the engine has no side to side wobble, both clamps are easy to get to and adjust, and once all 3 are tight nothing moves.

The main point however is how to get that to the pedal system.
Just a little engineering and metal work ;-}



Even on this tight Fito with 3" wide tires and extreme seat angle this design fits right in.

Both the pedal chain ring and 9T sprocket can be moved laterally for perfect chain alignment, and the little tensioner sprocket has almost no torque against it with engine power, or even with pedal power as the output shaft freewheels at the 100T T-belt pulley, and it is adjustable so no chain tension issues anywhere.

In fact, this 4-stroke shifting system is actually more sound than direct drive...
The drive chain is shorter and the tensioner much easier to keep in place.

Go figure I'd pull that off and with some luck have some for you guys to buy soon if you are liking this this solution ;-}
 
J

jhammondcpa

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Apr 17, 2014
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HI KC,

That is a sweet looking setup and good looking work. I am anxious to to see the package and might consider it on my bike!

Jimmy H.
 
KCvale

KCvale

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Feb 28, 2010
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jhammondcpa said:
HI KC,

That is a sweet looking setup and good looking work. I am anxious to to see the package and might consider it on my bike!

Jimmy H.
Click to expand...
Cool.
I should have 20 kits ready to ship in a month or so unless there is a flaw in my base design which we will know today when we button it up and test ride it hard.
 
Velodrome

Velodrome

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May 27, 2011
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Excellent! I hope to be an early adopter. Hopeing for one O them 53cc motors too :) My frame should be out of powdercoat this coming week.
 
KCvale

KCvale

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Feb 28, 2010
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Velodrome said:
Excellent! I hope to be an early adopter. Hopeing for one O them 53cc motors too :) My frame should be out of powdercoat this coming week.
Click to expand...
Cool.
Put up a pic of your frame and the measurement from inside the seat post to inside the down tube, level to ground, ~1" above the pedal sprocket, that will be your base length.

This Fito for example is only 7" but the stock engine with can exhaust and awkward air cleaner even fit.



Competence is high we can even get the stock chain guard on.


We had to trim the flywheel cover where the tensioner is and cut the choke lever down but she fits nice and solid.

This build won't go out the door this way.
Once it's running stock we are going to go through each and every combination of performance upgrades and document the results.

When this bike leaves, it will already have all the best performance mods on it.

That is if it leaves...
Sometimes I tent to hang on to things until I get an offer too good to refuse ;-}
 
KCvale

KCvale

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Feb 28, 2010
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The last tweaks to the drive train are done!



The cranks are just wide enough to the pass the covers.

The idler pulley works great and getting everything aligned is as easy as I wanted it except keeping the chain guard, just not enough room.



I have some black gas line and black tubing for the gas tank bolts to blend it in.

The end of the shaft has a threaded hole so I played with making a chain guard like the big sprocket, just enough guard to cover the sprocket teeth and the lid from a little bottle of capers was perfect.



I even made it a spinner, weighted the bottom so the KC would always read right when it stopped spinning hehehe ;-}

Anyway, I have a tach and speedo coming so I can run it through it's paces as I add mods.
 
KCvale

KCvale

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Feb 28, 2010
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buba said:
KC-- you are a maestro

could you share some info on the bicycle chains used for driving the rear wheel etc.
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Thanks ;-}
Nothing special for chains, from the dual crank sprockets the bikes 7-speed chain to the wheel and single speed 410 to the transfer case sprocket.

I don't care for derailleurs with a shifter, the thinner chain can be a break issue with a bad shift, and the chain is never straight expect for like in 3rd or 4th gear.

I like internal geared hubs, a Nexus 3-speed is just dandy even for a little 4-stroke. The chain can be nice 410 and it's always in line.
 
KCvale

KCvale

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Feb 28, 2010
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Skyking said:
What is the status of this kits availability for purchase. Do you have any kind of timeline on when they will be available?
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I am working on those very details right now.

It doesn't help that right on the heels of the month long CA dock workers strike the drivers of the container hauling trucks went on strike this week.

I am not importing any of this myself.
I am getting them direct from Don Grube after his container makes it to his new warehouse.

Until I have a $ number per unit to have everything here I simply can't state any price as I'm sure you understand.

I am thrilled with the interest in my new transfer case design but I'm just a normal guy that got something cool produced in bulk, how to price and conduct the business end I'm still working on.
 
KCvale

KCvale

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Feb 28, 2010
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All buttoned up and being test rode hard ;-}
http://kcsbikes.com/topic.asp?TOPIC_ID=861







I didn't like any of the digital speedometers I tried but did manage to get an analog to work, I mounted the spinner on the left with the disc brake.



The Tach/Hour meter is pretty neat.
It displays total engine hours when the engine is off, and RPM's when it's running.
It is idling in that pic at 4520 RPM.
I had it set fir 4-stroke mode but the HS engine fires every revolution so it doubled it.
Idles is ~2200 RPM

A little over 45 miles and 6 hours on it now.
The NGK 7544 (CR7HIX) Iridium spark plug is in and the exhaust changed out for a 2-stroke long pipe and it really woke it up.

I hit 38 MPH up a slight hill (Peoria Rd) in 7th bending over but not pedaling in 100F heat yesterday afternoon, and both the bike and I did it smiling like a silly kid hehehe ;-}

Velodrome said:
OOH! I would do a deposit to hold a spot in line. My ride for this is nearly done!
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Looking at mid June to early July before I get my first 20 units for sale and I still don't have a hard cost for them yet but $150 for a 10G long shaft is pretty close so you can reserve one with a refundable deposit @ http://KCsParts.com

On another note I am also working Don a design change for the GT2 gas tank bike frame to accommodate my 4-stroke shifting platform.
In short you can build it out to be a fat tire Fido with a real gas tank, dual discs, and a 3-speed internal shifter.

When I ride a 7-speed shifter I start in 1st, shift to 4th at redline, and then shift to 7th again at redline and the engine loves it.
A 3-speed internal would really make it a sweet machine for flatlanders.
 
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