First basic clone build

[copenhagen59]

I don't see any reason the flat top piston should be any tighter than the stock one. Hone the cylinder until you get a nice consistant cross hatch pattern on the whole thing. Assuming the cylinder bore is not in bad shape, this should be pretty easy, with a minimal amount of honing. Use plenty of oil, a slow drill speed, and don't over do it. If you pull the hone to far back while it's turning, the three arms are going to fly out. We used to use a Flex Hone "dingleberry" hone instead of the three legged spring loaded ones. I thought they were easier to use, and did a nice job, but you have to have the right size.

Yea I agree on the piston fit.

I'm planning on getting the 3 arm hone as I can get one for like 15 bucks from a local harbor frieght.

So I should use oil when I hone it ? If so what would you recommend?

And then I'm going to plastigauge the rod clearance before install. And use Lucas for assembly lube.

 

[RobK]

Pretty much any oil will work. Straight 30 weight is good for stuff like this, but any motor oil will work. Just use plenty of it so the stones aren't dry.

 

[copenhagen59]

Thanks guys for all the advice I really appreciate it.

So when I get all my parts installed and dialed in, How do you think it'll run? Compared to stock lol

Parts list,

ARC billet flywheel with 4 degree key (I'm going to lap it also)
ARC billet rod
Honda flat top piston (with new rings, wrist pin, and clips)
.010 head gasket with headstuds and heavy duty bolt/dowl pin kit
18lb valve springs
Uni air filter and adapter
90 or 92 jet
Bosch platinum 4 spark plug
stage 2 mini bike header
governor and low oil sensor removed
synthetic oil???
Maxforce Modified clutch

 

[Dual-500]

140 emulsion tube for the carb. You didn't mention raising the compression ratio. Is the piston flat top? With the rod and flywheel you have it will handle increased compression ratio. That will give you a good boost in performance and is a real bang for buck modification.

Since you're on a budget, get the head you have turned down. With a stock clone piston I did mine 0.077" and it made a huge difference. If you have a flat top piston going in, maybe not that far. Some of the other guys can advise you on that - I would guess 0.050" would be about where you would want it with a FT piston.

 

[copenhagen59]

Yes I'm getting a flat top piston as stated in my post above.

I don't really want to mill the head because I want to get it put back together soon and I want it simple as possible.

Do you think a 140 E tube would be worth the 15 bucks? Or just put the 92 jet I have in and check plug reading and be done

 

[Dual-500]

The clone I'm running now has the head milled 0.077" and stock piston/cam. Header on it with a canister muffler. It likes the 140 emulsion tube and stock jet. Much better low end and midrange with the 140 emulsion tube.

As was stated in posts above, you have done several longevity type mods. The head work will give it the most net power/torque gains and you have the baseline build that will stay together. The head is the bang for buck winner in overall performance increases.

Bringing the head down is simple machine work - any automotive machine shop could to it. The way these heads are made, the work can be performed easily on a lathe.

Bringing the head down doesn't change anything relative to re-assembly unless taken to an extreme - that's not what I'm suggesting. Just mild head work.

 

[RobK]

Keep an eye on Craigslist for a used Honda GX160 and use the head. I picked one up for $25. The 18cc head is going on one clone, and the flat piston is going in a GX200 real Honda I'm building. I've also already used the carb and coil on a friends MB165.

 

[Newoldstock]

Keep an eye on Craigslist for a used Honda GX160 and use the head. I picked one up for $25.

The rod and piston, valve train flywheel is all better quality than the clone and bolts right one.

Often overlooked and forgotten is the Clone valves, keeper and retainers are generaly pretty soft and will start to wear and come apart with a clone even running at governable speeds as low as 5000 rpm.

The GX160 flywheel is better quality iron and has a built in 4 deg of advance over the stock clone parts too.

This does not mean you can rev the shit out of the engine with these better quality parts but you do get a little more piece of mind.

You added info.....
The GX160 carb is smaller than the clone.
This will actualy cost you some power.

 

[copenhagen59]

Is it really necessary to vent the block at my power level ? Or is the valve cover breather sufficient ?

 

[Dual-500]

Is it really necessary to vent the block at my power level ? Or is the valve cover breather sufficient ?

For what you are doing the stock valve cover breather vented into the intake is fine.

 

[copenhagen59]

Well guys all of my parts have finally arrived and I'm pretty excited :smile: .

One of my instructors who builds these engines for race karts told me he has a dingleball hone I can borrow. He told me I should have about .003 piston clearance when I get done ?

So basically if I get it honed and the plastigauge on the rod is within spec, It'll be getting built soon!

 

[Newoldstock]

Well guys all of my parts have finally arrived and I'm pretty excited :smile: .

One of my instructors who builds these engines for race karts told me he has a dingleball hone I can borrow. He told me I should have about .003 piston clearance when I get done ?

So basically if I get it honed and the plastigauge on the rod is within spec, It'll be getting built soon!

Personaly if the engine is used I would run a flat stone hone because it will know down any high spots.

But to each his own.....

What rings did you order stock or file to fit?

 

[copenhagen59]

Personaly if the engine is used I would run a flat stone hone because it will know down any high spots.

But to each his own.....

What rings did you order stock or file to fit?

Stock. I've already got it honed and in the cylinder.

Now I'm going to have to make a run sometime to get a 1/4 inch drive torque wrench because I've found out theres no way I'm going to fit my 3/8 inch drive in there with an adapter lol

 

[copenhagen59]

Well guys I got it rebuilt and running :thumbsup: .

Everything seems to be normal and it feels like it has a ton more power.

It still lacks a few odds and ends but it's pretty well complete. I do have one question though,

Should I put a lash cap on my intake valve? or should it be okay

 

[Newoldstock]

Well guys I got it rebuilt and running :thumbsup: .

Everything seems to be normal and it feels like it has a ton more power.

It still lacks a few odds and ends but it's pretty well complete. I do have one question though,

Should I put a lash cap on my intake valve? or should it be okay

An exhaust valve retainer and lash cap would be a very good idea.

Nice job and keep up th egood work.

 

[copenhagen59]

Well I did put an exhaust valve retainer and lash cap on the intake side.

And yesterday I took it on a long ride and I'm very pleased. It runs smooth, has alot more top end, and mainly TONS of torque over stock lol.

The highest RPM I've read so far is about 6,800 But I think I can hit 7 if I make my throttle linkage a lil better because I don't think it's opening up all the way.

I've broke it in with conventional 10w 30 Valvoline. But I'm considering switching over Mobile 1 synthetic 10w 30 .

Do you think this is a good idea? I've heard alot of other people use it with good luck, but I've never ran anything on sythetic.

Is going synthetic now the best for the engine? This one I'm not sure on

 

[copenhagen59]

Also the plug reads just a light tan color. I runs good but you have to give it throttle just to start it even with the choke on.

I've been thinking about swapping out my 90 jet for a 92 since I have an extra.

Do you think this would help my issue? and maybe even make more power???

 

[Dual-500]

Did you put a 140 emulsion tube in it?

 

[copenhagen59]

Did you put a 140 emulsion tube in it?

No I did not. Will it help or just run too rich?

 

[Dual-500]

No I did not. Will it help or just run too rich?

The clone I'm running now has the head milled 0.077" and stock piston/cam. Header on it with a canister muffler. It likes the 140 emulsion tube and stock jet. Much better low end and midrange with the 140 emulsion tube........

Bump.