[Ben Lewis]

I’ve used both the PWK and PWM and I’ve noticed that the PWM is very sensitive to a fat pilot jet down low and I’ve experienced this too on occasion. Then it disappears after like 3-5K and rips. Does it get better or worse as the day gets hotter/colder?

I’ve also had electrical problems give this symptom too. Check your connections and solder them so they have no change to wiggle.

[Ben Lewis]

+10 on the seat good advice here. I can barely fit in mine but then as soon as I get moving I don’t even notice.

Run c12 you’ll be glad you did. When I first started w the S-M 125 I used 98 pump gas and after 6-8 weekends had a detonation ring which made both the head and cylinder worthless. That was over $350 to replace. I generally run 4-5 15min sessions on a practice day and rarely use more than a gallon to gallon 1/2. At ~$20 a day in gas for the c12 it’s a good investment. Plus if you’re planning on tuning a pwk/pwm with the right jetting race gas will help a lot in giving you stable readings.

[Ben Lewis]

Cool Rob thanks for the reply. Yeah I think that would be a good idea for (Norcal) shifters to put up a note on what local races they’ll be at. But only for club races. I think we can assume people are going to show up for a SKUSA event :)

The Stockton 2017 schedule is up search ‘Stockton little 99’ and go from there. The first race is March 05 so it’s coming up. It’s a coin flip whether it’s going to rain or not. Personally if it’s raining I won’t go. Not worth ingesting water into my new rebuild engine.

[Ben Lewis]

Ok I feel like the point is being missed here. Yes I know about Sonoma and I go there all the time. I also know about every track and series run in CA. This thread is for people who might be interested in showing up w/ their shifter for some more relaxed, fun, and cheaper racing at STOCKTON. All shifters right now are being run in the open class and as of the last race I was the only shifter in a field of 40-50! The point is I don’t want to have to pay the huge cost of a race weekend in any of the major series not to mention to get a legal engine package would be 3-5K alone. I know there are plenty of weekend warriors out there looking for a chance to dust off that 80 or 125 shifter (heck bring your Tags) and race without going through the huge cost to be competitive in the major series and chasing points.

[Ben Lewis]

Cool Bob thanks for the reply. You say you’re getting into stock moto? That’s basically what I run. Except I use Wiseco rebuilds cause they’re cheaper. Have you ever run a full series before, moving from TAG?

My whole point is I know that Infineon will always be a better track esp for the shifters. But, because right now shifters are run in the ‘open’ class at Stockton the rules are a lot more flexible so it’s a great venue to shakedown your setup or have fun racing on a budget. Problem is there is no consistent shifter field except me. I’ll be doing at least 6 events hopefully more. Hope you make it out to at least one race!

[Ben Lewis]

Also I just started a Youtube channel and am finally uploading some videos. There aren’t a ton yet but check em out. I plan on doing a few how to videos in the near future and am currently in the works on a few. I will be uploading a lot more content so keep a look out Suggestions are invited too I need some ideas or things people want addressed. Thanks!

 

https://www.youtube.com/channel/UCaTSRaXbcXwALHGDYJeodGQ

[Ben Lewis]

My 2 cents.

I’ve tried many different engine combinations and I personally run a cr125 in ‘stock moto’ trim under a similar but newer chassis (Birel cry32). I absolutely love it but you said you are new to karting… I have seen many people jump into the deep end with a cr125 shifter and jump back out just as quick. It’s a great setup, reliable, fast, easy to work on and cheapish. BUT in my opinion for someone starting the cr80 is the way to go. You will have to remove the front brakes if you want to compete but you said you didn’t. Cr80’s are not nearly as brutal as the 125’s and are much cheaper prob 1/2 the cost. You will learn to drive and have much more fun out of the gate. They are also a good engine to learn to do rebuilds on. Being able to rebuild your engines is a huge $$ saver if you plan on spending anytime in the sport. Then after a couple of years if you want more speed you can always upgrade.

Frame spacing is NOT the same

it will be:

30×90  or 30×92 or 32×90 or 32×92

Most Birels are 32×92 but you neeeed to measure. Look on Youtube.

In my opinion (its just my personal thoughts ok no one get pissed) the Tag motors are much too $$ and finiky for someone new. They are not nearly as do-it -yourself look up a rebuild cost and then imagine paying that every year. However they do make some of the best racing out there too.

The KT: great lil engine but you will have a very hard time selling it once your done.

Whatever you do make sure you get up to speed on 2t basics they are crucial in karting and all of the engines your looking at will need tuning day to day.

Also whatever you do make a yearly budget! You will need to replace things every winter. A lot of people get frustrated because they think pistons, gaskets, bearings, chains, clips, cables, fuel line, brake pads all last forever. They don’t  they are consumables and it only takes $4-500 dollars at the end of the season to freshen up your chassis yourself.

Let me know if you get a cr80 or cr125 I have a wealth of knowledge and yes there is very little info out there for the first timer.

Hope you catch the bug!

 

 

 

[Ben Lewis]

I know I’m late to the game on this post but for anyone else who looks at this down the road for reference:

Throw the PJ away! Or sell it on ebay. You will always have issues.

Get a PWM and start with (Sea level):

DGJ needle 2nd clip (never move clip its good at 2 forever)

M168 65-75 degrees

M165-162 80-100 degrees

Pilot 54-55

*These are baseline ref only

You can sometimes pick up a cheap PWM by searching for a mid 90s YZ250. I think they also came on a few other bikes stock. Also, a common mistake is to give too much gas when push starting. Don’t give it any until you hear bah dump dump and then only give it a little. And never ever pump, you will flood it every time.

Make sure your throttle adjustments are set so that without pushing the gas pedal there is just a crack of opening between the slide and barrel. Just the teeniest bit.

Sorry to sh** on the original question but I’ve messed with the PJs before and its just not tune-able esp with a kart pipe.

 

 

[Ben Lewis]

Hi Jose,

I’ve been running the ‘stock honda’ package for 3-4 years now and I’ve been karting for much longer, so I hope I can pass on some knowledge. One of the (only) downsides to this class is that there is a real lack of info say compared to a 206. Hope I can help.

Jim is right it sounds like the shift lever doesn’t have enough throw. Make sure that the J-arm which connects to the shift shaft on the motor is as close to 90 degrees to the ground as possible. If it is leaned forward too much it will bind. Also, one thing I’ve noticed with novice drivers is that they let off the gas waaaay too much when up shifting. It only takes a 2-300 rpm drop to up shift, which basically translates to the blink of an eye. I also notice that new drivers tend to bounce their throttle foot. There is a back-forward motion on the up shift and its very easy to hit the gas premature and miss the shift. This might explain the rev. Double throttle springs are a good and cheap buy. Another trick is to shift by ‘squeezing’ with your fingers while your thumb is still wrapped around the steering wheel. Not only is this quicker but less fatiguing. And yes the #1 cause of missed shifts is fatigue!

Down shifts should use NO gas until you are the master of late braking, and then it’s only a teeny bit and corner specific. Fyi in my opinion learning hard threshold braking is one of the most overlooked skills for new drivers. Any guess to where 8/10 passes happen?

The CTS chassis are good but they weren’t produced in large numbers. I believe they take Unico style body work. But look up the measurements online and compare to your chassis.

Also what carb are you running? If you have the stock PJ your will deff be running out of top end. PWM is the way to go in my opinion and they can be had for a little cheaper by searching for a mid 90’s Yz250 carb instead it was stock on that bike I believe and maybe a few others.

Other top end killers:

Fouled plugs should be new Br9eg or Br10eg

Bad reeds

Electrical. Solder everything! Connectors are convenient but they fail.

Exhaust. Leaks and cracks will do weird things to the mixture and make it very hard to read.

Lastly Jetting!!!! This is one of the finer points and needs a lot of trial and error. Go slow and read your plugs.

What is your Fuel:Oil ratio? It should be 24:1

Hope that helps.

[Ben Lewis]

Thanks for the quick reply

I know the cr500 isn’t legal but the yz125 isn’t legal in Stock moto. Doesn’t mean its not a great or even better engine. However, I don’t know if Honda has a spec deal in super karts like in Sprint.

But, a tuned cr500 can make almost 80hp on alcohol and probably twice the torque of a 250 so it still seems like it would be a good step in between the 250 single and double.

I didn’t know the 257 was making those numbers. Quite impressive actually. Is there a good supply of parts in America to support the 257? I’ve done some looking and parts are out there but seem to be spares every one is getting rid of… makes me wonder if that formula is dead or dying.

Makes sense on the wing. There aren’t nearly as many tight slow speed turns on a road course. And with little to no Ackerman the lifting effect would be reduced anyways.

Anybody else currently racing have input?

 

 

[Ben Lewis]

Think I’ll chime in

Go for it!

I did this too and it was a blast. Keep in mind you need to add +20% to your budget. Even if you are mechanically inclined doing this for the first time you will mistakes. But, that’s part of the fun. If you plan on doing this for a while then build it first yourself. Rebuilds again and again once you’ve got the bug will save you way more than your first build will. Plus you can put a sticker on it with your name and people will say “hey I never heard of Lucastech”. It seems to me that Stock moto should be about the club guy who can build his own stuff that’s one of the main reasons I chose it…plus there’s some real speed there too.

1)Don’t skimp on the radiator you don’t have to go out and spend big $ to get a quality one. Don’t be tempted to try and mount a rotax banana style or 1 dirt bike radiator. The cr is more demanding with that big hot pipe in front and heat = death. Do not run without at least a trailtech temp sensor.

2) You will also need the kick start plug. I run mine without the idler gear IDK if others do. I’ve done 3 tops and a bottom and its been fine. 1oz weight savings! Hoorray

3) Absolutely do the slip fit on the crank it makes rebuilds a breeze. If you are putting it on a lathe make sure the crank is secured from swinging out. Duct tape will not do the job. Safety wire will just don’t put it through the bearing surfaces.

4) the 96-97 is a direct swap. I’ve done it but they are hard to find. It took me 6 months to find a cheap one that wasn’t abused.

5) The 99 CDI is going to be $$ too. You’ll have to go to a kart shop for this

6) You didn’t say if you were racing or not. If you aren’t the Wiseco kit is cheaper and has predrilled holes for the exhaust rib. And it’s more durable imho.

7) Don’t try and fit this to the L206 chassis. You need a 32mm shifter chassis. I used to race l206 and then some jerk let me test drive his S2. Now I’m hooked for life. It’s a big curve make sure you drive one first. I’ve let several friends try out my shifter and they were like nope ok the TAG is good for me.

8) There is much more to this setup than just the motor. This package has a lot of ancillaries. J arm, Shift shaft, Kart Clutch cable, Motor mount, engine stop, Air box (don’t do filter many tracks are banning them), air box mount, as many seat struts as will fit 4-5 is ideal, chain guard, pipe mount, silencer mount…

Let us know how it turns out! It is very do-able and you will be sweating like heck but smiling inside that helmet. Mine came in around $1500 with a full rebuild included.

Top tip: start doing pushups now

 

 

 

 

 

[Ben Lewis]

Here’s some pics for motivation

This is what you don’t want

Here’s the (almost) final product

 

[Ben Lewis]

[Ben Lewis]

I may be a bit late to this thread but I recently have done this conversion. The engine i got was already attached to a kart but was very much in dirt bike form with little done to it but bolted in. I decided to take it in a stock moto direction (even though it’s a 96 and wouldn’t be allowed). Here are some basic things you’ll need to consider doing:

1)Rebuild everything!!! Top end and bottom. This will save you headaches. Trust me on this I thought I could just do the top end because the play in the crank was within tolerance and BOOM shrapnel from the bottom end going bad ruined my day and added $500 to my budget. Then I had to rebuild anyways.

2) Remove the power valve and put some blended plugs in. Not only will this give you better Kart specific power up top but will keep the power valve cover from wearing through your nice exhaust since the stock one will be removed.

2) Plug up the hole in the case you just created removing  the power valve with a unit that Fastech will sell you. Use  a little RTV around the collar even though it rests on a seal anyways

3) Remove kick starter and plug it with another billet seal

4) Find a place to mount the coil I did mine off the case with a little swedetech unit

5) Buy a pipe and mount. Ive got the ‘old’ RCE its sweet

6) Get an o-ringed exhaust manifold. They are well worth it.

7) If your going to do the weekend warrior thing get a wiseco piston kit they have 2 little holes that lubricate the rib to help w/ sticking

8) Get a side cover for the stator side (swedetech)

9) Run a y-hose or do what I did and block off one of the water outlets on the head.

10) Run a water temp sensor. Trail tech sells an awesome little unit.

11) Decide if you want to run a UNI filter or a box. Personally I run a UNI

12) Buy a PWK/M carb and run a pump around or figure out a fueling setup. Look up Tiger Racing’s Poor mans pump around. I use a pressure regulator and a return in this fashion. It would never race but works pretty good for track days.

Lastly you’ve got to have a proper chassis/mount to put it on and all that comes with that. All these steps have little details that really add up. I would estimate that without learning mistakes I’m in at about $800 for the conversion after the $500 motor. With mistakes and its approaching 2K all together. A savings sure but whats your time worth? It can be a lot of work but personally I like a little pain with my enjoyment. Yes you will get very familiar with tearing down the CR, and in relative terms it’s quite easy and cheap to work on. This is why I chose this setup because its way more involved and you can do the work.  But, you gotta like that sort of thing or it will drive you mad!!  I wish you luck and post pics when you’re done

 

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