Measuring deck height

[bob58o]

Why are you using heat range 9 plug? It’s a cold plug. 3 ranges colder than stock. Get a BP6ES, plug and see if it still fouls out.

 

[BrownStainRacing]

@BrownStainRacing I did some testing with the same jetting size and I don’t have numbers for amount of time to get from idle to WOT but I do have some qualitative information.

Based by adjusting the idle/air for highest idle, I get the highest idle rpm at 1.8 - 2 turns out, going from 2k at a little bit past 2 turns out to 2.5k at 1.8 turns before going back down in idle rpm.

Loosening the screw gets the engine sounding almost like it’s chocking out(this is at around 2.5 turns). I checked the plug after running it for not even a minute and it was completely fouled up, carbon buildup.

So unless I’m doing something wrong, it likes being leaner

RPM engagement of ~ 3000


*** One thing I realize is that there is a high possibility that the stock t/c on the go kart is a Chinese off brand***

I attached a video of WOT, turning max rpm of 5800, hopefully works

IMG_4798.MOV

drive.google.com

It's definitely not falling on its face!!!!

There's still something going on with the low side.

Try a .035" main jet.

Look on the main body of that carb for a brand.

ARC only makes "made in Japan" or "RuXin" carbs into SA bored carbs, unless they changed.
I'm hoping OMW didn't do a switch a-roo on you or accidentally sent you the wrong carb.
I trust nobody.

Look at the stock carb too.

It's making the power, you can hear how fast it's moving the t/c into high and pulling the rpm up fast.

Most will drop rpm when it goes into high and never recover.

Set it where you think it's best with a .035" main jet, you got a good ear, tach and temp gauge to help.
Install a new plug and run it hard to get temp in the engine, temp is part of the tune. That PVL flywheel keeps it cool, maybe too cool.

Get another plug reading, watch for a max temp, and we can move on from there.

Good job!!!

 

[BrownStainRacing]

Why are you using heat range 9 plug? It’s a cold plug. 3 ranges colder than stock. Get a BP6ES, plug and see if it still fouls out.

His build is a lil more then stock.

I tune with a ngk bp9es and run a autolite 3910x after I get the tune, with modified builds.

I find the tune quicker with a cold plug.
That's probably jus yrs of playing with that sbc, hei distributors and holley carbs.

 

[BrownStainRacing]

Why are you using heat range 9 plug? It’s a cold plug. 3 ranges colder than stock. Get a BP6ES, plug and see if it still fouls out.

I'm not saying DONT try it, it's jus a plug change, test run, and reading

1 or 2 heat ranges will have a different reading. But I don't think that's his problem. There I going thinking again,

That thing should fire off like a chainsaw, from idle to WOT.

He's got the mid range and high side hitting like a wrecking ball, it's that low side, very slight hesitation im seeing.

I'm positive he can work it out.
When he does, he's gonna be ordering rear tires by the dozens,

 

[BrownStainRacing]

@bob58o
@atlantazombie

Blower/charger, Ignition timing, lean/rich, WOT, CR

Guide to Understanding Spark Plug Heat Ranges

You may usually ignite the compressed fuel/air mixture by a spark plug, but do you really understand the spark plug heat range? To make things easier and to

carfromjapan.com

 

[atlantazombie]

It's definitely not falling on its face!!!!

There's still something going on with the low side.

Try a .035" main jet.

Look on the main body of that carb for a brand.

ARC only makes "made in Japan" or "RuXin" carbs into SA bored carbs, unless they changed.
I'm hoping OMW didn't do a switch a-roo on you or accidentally sent you the wrong carb.
I trust nobody.

Look at the stock carb too.

It's making the power, you can hear how fast it's moving the t/c into high and pulling the rpm up fast.

Most will drop rpm when it goes into high and never recover.

Set it where you think it's best with a .035" main jet, you got a good ear, tach and temp gauge to help.
Install a new plug and run it hard to get temp in the engine, temp is part of the tune. That PVL flywheel keeps it cool, maybe too cool.

Get another plug reading, watch for a max temp, and we can move on from there.

Good job!!

OMB carb is keihin and got number 64YAM023.

My old carb was yinba.

I put in the .035, left everything else alone. I did a couple tests idle to WOT at operating temp and it still seems to like 1.8 - 2 turns out, not leaving any rubber behind. Tested in 1/8 increments from 2.25 to 1.75 turns. Also the idle rpm is still higher at ~2

then put in plug, no difference. I didn’t change the air/fuel tho kept it at little under 2
Top rpm was 5800, then drops to 5k before topping out at 5200

My brother wanted to hop in as well(80lb) so that would ~235lb combined, and the kart had a crazy jolt from idle to WOT, almost like it was pulling even harder! Maybe it’s something as simple as more gear reduction

Temp was ~235f cruising around at higher speeds, ran a couple doughnuts and it hit 265f

PCV system is holding up, it does have a very small oil accumulation on one of the threads, the one where I made the additional hole and doesn’t have many threads to grab onto.

The driven side of my t/c has a nut that keeps getting loose, I impact driver it to tighten it, but got loose twice so far. Thinking of just loctiting it.

Got around 40-45 mins of driving on that new plug, didn’t change nothing besides riding it in

 

[BrownStainRacing]

OMB carb is keihin and got number 64YAM023.

My old carb was yinba.

I put in the .035, left everything else alone. I did a couple tests idle to WOT at operating temp and it still seems to like 1.8 - 2 turns out, not leaving any rubber behind. Tested in 1/8 increments from 2.25 to 1.75 turns. Also the idle rpm is still higher at ~2

then put in plug, no difference. I didn’t change the air/fuel tho kept it at little under 2
Top rpm was 5800, then drops to 5k before topping out at 5200

My brother wanted to hop in as well(80lb) so that would ~235lb combined, and the kart had a crazy jolt from idle to WOT, almost like it was pulling even harder! Maybe it’s something as simple as more gear reduction

Temp was ~235f cruising around at higher speeds, ran a couple doughnuts and it hit 265f

PCV system is holding up, it does have a very small oil accumulation on one of the threads, the one where I made the additional hole and doesn’t have many threads to grab onto.

The driven side of my t/c has a nut that keeps getting loose, I impact driver it to tighten it, but got loose twice so far. Thinking of just loctiting it.

Got around 40-45 mins of driving on that new plug, didn’t change nothing besides riding it in

Keihin is Japan, so that's good. Theres no telling what that other 1 is, .
If you have extra carb gaskets, and isolation plate, you can try that stock carb. You never know, til you try.
At least you will see the difference with a stock and a SA bored carb

You have it right there at the transition from low to high. Thats a tricky fine line with the SA bored carbs, it's jus a matter of tuning, more test time, and plug readings.
You probably bout outta plugs,
That's why I start on the lean side and go rich, usally only need 1 or 2 to plugs.
You can back out the low speed mix and up the rpm OR... go the other way.
You are really close, so dont get crazy with the screwdriver, .

Keep an eye on the plug til you get the best reading for the high side. Then work on the low side.

If you turn low speed mix out and it drops 100 rpm, then turn idle speed up 100 rpm.
Same as the other way, it goes up, turn idle speed down.
It might want more OR less rpm idle speed, it's far from a stock tiller motor so I know it's not gonna like a tiller tune.

265* is too cool, we will get to that later.
That PVL flywheel cools too good. If you read the description and instructions for it, they tell you what to do. That's for box stock racing builds...... you are WAY passed those.

After a good hard run, it should be steady 225-250* at idle, after it set for a min or 2 at 2000+ rpm.

Might need to back the timing down 2* to put more heat in it.
As long as your plug is not blistered white, you are in the safe zone, for now.
You need to verify your timing the next time you have the driver off, before you go twisting the flywheel, sounds too easy huh,

That 10.6:1CR and faster ramped camshaft, might be too much pressure for low octane fuel. Backing the timing down or running more octane will solve that problem.
But verify where you are at 1st.

PCV, you can put some JB weld on those bad threads and let it set over night, it won't take much. Take your valve cover off so you don't get any jb weld loose in there.

If oil is seeping out, then air is getting pulled back in when piston goes from bottom to top, thats defeating the purpose of the check valves.

I make a lock to lock the bolt down for the 20 & 30 series drivers.

Working with modified engines you will be pulling the driver often to set up gear ratios, stall speeds, adjusting driven spring, and checking those side cover bolts or studs. Until you get it right, and you never have to worry about it again.

Lock tite will eventually booger up the threads in the crankshaft or you can keep running a tap and cleaning threads.

This lock fouls the bolt and it will never come loose again.
Ez to get on and off, it's a stupid simple lil thing. A flat washer with a couple folds in it.

I'll see if I can round up some pics for you.

I don't recommend it for stock boring engines, lock tite will be perfectly fine and last for years.

The driven nut needs to be a nylon lock nut and they will unlock when the nylon wears out. It don't hurt to have spares in the shop.

Again, I don't recommend lock tite here, but it's yours and you can do as you please, .

I think you are way over geared with the built 196 you have now.

The stock 6.25:1 gear worked good with a stock engine that made around 9 ft/lbs of torque.
I'd say you are closer to 12 ft/lbs now.
You can worry about that after you get the lil bugs outta it.

Did you try 2 pink springs in the driver yet???
It should be around 2800, but those China scales must change everyday, because those China flyweights are never the same weight.

The set up might like 2800 over 3000, don't know til you try.

Keep tuning, you'll get it, i have faith in you,

 

[atlantazombie]

Got sum more plug readings, on the .035” jet. One with the red arrow shows the color change to white, about 1 hour on that plug.

I pulled the plug again after some more riding, that is the plug without the arrow

 

[BrownStainRacing]

Needs a lil bit more rich on the low side.

Up to temp, adjust out, til it puffs black smoke, then back in a hair or 2, test.
It might like a lower idle speed, with the .020" low speed jet.

 

[BrownStainRacing]

@atlantazombie
Here's some pics of rockers, pushrod lengths, different thickness head gaskets, lash caps.

There so many things that can throw the valve train off.
Valve seat depth, valve length, pushrod length, lash cap thickness, quide plate slot, rocker ratio, head gasket thickness.
These are mass produced parts, nothing is the same, trust no parts, always double check when buiding a modified engine.

You can take all your parts off and put on another block, and nothing will be the same. That's jus the way it is.

I hope I can keep em order.
These are all checked at TDC, lifters on base circle of cam (valves closed) at .000" lash.

The 1st is hemi lifters and pushrods with non hemi head, thin gasket, no lash caps.

You can see the rocker slot is already on the the stud and there is no room for lift, I cannot turn the engine over without bending a pushrod, stud or breaking a rocker.


Heres hemi lifters, clone stock length push rods, thick head gasket, no lash caps.
The rocker is almost straight with the edge of the head, but still not right.


Heres different thickness lash caps. Getting closer, the rocker slots are away from the stud and theres plenty of room for lift now.



Here's a stock 196 I'm tearing down.
Thick gasket .045"-.052", no lash cap.
The rocker is level with the gasket surface of the head.



Always check these at .0" valve lash.
Rocker to retainer clearance at valve close and max lift.
Pushrod to quide plate clearance, front to back, valve closed and at max lift.

And always check coil bind at max lift.

After all these are checked, and double checked, set valve lash to .003". And check again to make sure.

 

[BrownStainRacing]

@atlantazombie
Here's an example of these engines being way different.

Your 196 piston was .040" down in the hole.

This 196 piston is .009" down in the hole.

This is a 2012 baja engine, never been apart, only upgrades I did was 212r flywheel, and main jet.
Ran great, started on 1st pull every time, no smoke.

Looks like I got a 18cc head off it, that's a good score.
After a cleanup and unshroud the valves it should come out to 19-19.5cc.

I'll save it for a 212 or 224. This 196 will get a 14cc head.

All the oil looks to be from the piston to cylinder clearance, and ring end gaps not in spec. The intake runner is dry and clean, so I know the valve guide is good.

 

[atlantazombie]

Alright my exhaust valve length measures as 2.45” and intake as 2.52” jus for when I need it

Racing Cams and Parts | Ducar Exhaust Valve | CL-1125 | DynoCams

The CL-1125 Exhaust Valve is a Ducar OEM clone part for 196cc OHV clone engines. | CL-1125

www.dynocams.com

Racing Cams and Parts | Stainless Steel Exhaust Valve | CL-1126 | DynoCams

Explore a World of Parts: Find the Components You Need for Your Projects. From Mechanical to Electronic, Discover a Vast Selection of High-Quality Parts to Fuel Your Creativity. | CL-1126

www.dynocams.com

First one 2.445” other is 2.448 inches long.

Im also getting 2 new rocker studs, the other one was slightly bent as well.

2 new valve springs
New 14cc head form Omb
Piston rings (already have a good spare piston)
-0.04” pushrods, chromoly ones were just 3 bucks

should I get thinner and thicker lash caps in case I need to change anything around?

 

[BrownStainRacing]

Alright my exhaust valve length measures as 2.45” and intake as 2.52” jus for when I need it

Racing Cams and Parts | Ducar Exhaust Valve | CL-1125 | DynoCams

The CL-1125 Exhaust Valve is a Ducar OEM clone part for 196cc OHV clone engines. | CL-1125

www.dynocams.com

Racing Cams and Parts | Stainless Steel Exhaust Valve | CL-1126 | DynoCams

Explore a World of Parts: Find the Components You Need for Your Projects. From Mechanical to Electronic, Discover a Vast Selection of High-Quality Parts to Fuel Your Creativity. | CL-1126

www.dynocams.com

First one 2.445” other is 2.448 inches long.

Im also getting 2 new rocker studs, the other one was slightly bent as well.

2 new valve springs
New 14cc head form Omb
Piston rings (already have a good spare piston)
-0.04” pushrods, chromoly ones were just 3 bucks

should I get thinner and thicker lash caps in case I need to change anything around?

Get both. After you get em lapped to seat you can see which ones gonna work best, probably the longer one, who knows. Ive used both for builds.
Your valves are 5.5mm stems. So order caps that fit the stems.

I get the caps from different suppliers, to get different thicknesses. It's a hit and miss thing, you never know for sure what you will receive.

Get retainers too. 2 exhaust, so you can lock em in.

 

[atlantazombie]

While I’m back in the engine do these con rod bearings look good to you? Don’t want anything seizing at 5k

 

[atlantazombie]

Get retainers too. 2 exhaust, so you can lock em in.

I already got the old ones, should I put them in the “for later” bag?

 

[BrownStainRacing]

While I’m back in the engine do these con rod bearings look good to you? Don’t want anything seizing at 5k

I've used worse, you can clean that up with a scotch pad.

I change bearings and bolts every 3rd piston and ring set, they're cheap enough for extra inaurance.

Get another 1, there's no such thing as too much inventory when it comes to these engines.

I see you got the long slot guide plate, that's better then the square one.

 

[BrownStainRacing]

I already got the old ones, should I put them in the “for later” bag?

Retainers are like everything else. Different thicknesses will call for different spring shims.

 

[Denny]

Do not scotch brite the bearings! All it does is embed hard junk into the bearings! Buy new ones, their worth the peace of mind!
I had an uncle who was a bearing salesman for Clevite. He told me their engineers could not believe people were actually doing that. It ruins the bearings.

 

[atlantazombie]

I went ahead and just blending the port to bowl transition on my new 14cc head. On the short turns and next to the valve guide, and then the bowl to valve as well. Didn’t take too much out. What sort of bit should I use to “smooth” out the intake? on a different older thread I saw @bob58o using 80 grit on the intake. Third pic is a sanding bit I have lying around. How do y’all go about porting?

 

[BrownStainRacing]

I went ahead and just blending the port to bowl transition on my new 14cc head. On the short turns and next to the valve guide, and then the bowl to valve as well. Didn’t take too much out. What sort of bit should I use to “smooth” out the intake? on a different older thread I saw @bob58o using 80 grit on the intake. Third pic is a sanding bit I have lying around. How do y’all go about porting?

Don't open up the runner, jus knock the sharp edges off where the gasket sets.
Make the runner as rough as possible.

I agree, 80 grit works. But dont make your lines straight, keep em swirled, jagged, zig zagged, circled, criss crossed,......anything but straight.

Here's a perfect intake runner.
I wouldn't pay for it, but that's me. He actually hoggs the runner out, reshapes it, then epoxy's it.

But you can see how rough it needs to be......WITHOUT OPENING IT UP.

https://www.paulskarts.com/product/epoxy-port-small-block/431

You need more work around the valve guide.

Get those steep drop off's to a nice slope, and reshape the valve guide.

I make it pointy at the top and fat at the bottom, shape it to a tear drop pointing to the runner.
Some others make it a high shark fin, some with a shark fin with a slight curve.

I don't have time to shark fin, curvy, dimple the runner like a golf ball, jeez....it jus a "turd motor".

Bits, is a perfered thing. I start with a carbine, squared, round, tipped whatever it takes for the rough stuff, and done with rolls. 20-30 mins a runner and it's done.
Soapy hot water wash, blast with brake clean, lapp the valves, set install height, add springs and retainers. Done and last for years

Here's 1 started with sanding rolls.
I have no idea how i ended up with it, but it is no use to me, the chamber is too big.