Ghost or Predator with hop-up?

[Wicked_Daddy]

Wow, just wow. All the info needed to do this! I like the kit from OMB - has everything for a great price. I will add 22lb springs though. 18 just seems light for safety sake. I like the idea of adjustable timing as well, with the coil mount. Great find! I will definitely add the carb as well and I like the extended, curved manifold. The length should add some torque.

I will keep the CVT for now and mount it on the engine at whatever angle gives it clearance above the axle sprocket. The seat does not need to move. There is plenty of space. I can also move the engine mount forward some, as it is a mount that clamps to the frame and can be positioned more forward or back.

It may be a week before I get the parts, do the build and mount everything. Pics will be thereafter.

 

[Wicked_Daddy]

Zen and The Art of Motorcycle Maintenance

THIS! I have a well read, 4o year old version on my book shelf.

 

[Wicked_Daddy]

OK, so I have ordered the kit (piston, flywheel, cam, rod, springs, etc) Looks like I will need a better exhaust so that too: 1 inch pipe. The only thing left is the carb. I am seeing stock carbs that are bored out or the slide carbs. I'm thinking a 24mm slide - but which one? Anyone have a Nibbi? They look reasonably priced, less than a Mikuni, more than a Chinese clone, and get decent reviews. And, hard to find what seems like a proper cable for it. "Mikuni" cable for sure... but they all seem to be for mini-bike throttles. Ugh. Just cut that end off?

 

[Whitetrashrocker]

I like the Nibbi. Well made clones.

 

[Edwin Spangler]

Anyone have a Nibbi?

Ive had a couple. One on a 212 and one on a 140cc ZX motor or something. Theyre good quality.

 

[Wicked_Daddy]

I'm a little disenchanted with the hot rodding process on this Lifan engine. Makes me think I should have just bought a Ghost and been done with it.
- The Lifan is pretty well built though - steel cam gear (wasn't expecting that) was a pleasant surprise, even though I am replacing the cam. No governor parts at all. The castings are there for oil sensor and governor items but they were never used - no holes to plug or things to remove.
- Comparing the piston rings of the original to the aftermarket reveals the OEM are very robust compared to aftermarket. The aftermarket are very thin and have very little outward tension. So I kept the original piston and rings (barely past break in, if at all).
- Valve springs were already 18lb but I got 22. The nuts on the rockers were so tight that one of the studs broke trying to get them off. So now I have ordered a Champ rocker set that come with bolts. Ugh.
- Upon torquing the head bolts, 2 of them would not torque - just kept going. So I thought I was probably stripping the block but when I pulled them out, they were stretching and were probably close to breaking. Crazy. The torque spec is only 17ft lb.

I thought this would be a couple hours of build time. The billet rod and 275 cam are in. I had to go out and get a 1/4" 12 point socket because I had every socket in the known universe except that one. ARC couldn't just use hex?! Flywheel was easy. No issues there. Gotta get my hardened head bolts and rocker set and then finish it up.

This thing had better kick some a$$.

 

[Denny]

it won’t. It can’t lift its little leg that high!

 

[Edwin Spangler]

I'm a little disenchanted with the hot rodding process on this Lifan engine. Makes me think I should have just bought a Ghost and been done with it.
- The Lifan is pretty well built though - steel cam gear (wasn't expecting that) was a pleasant surprise, even though I am replacing the cam. No governor parts at all. The castings are there for oil sensor and governor items but they were never used - no holes to plug or things to remove.
- Comparing the piston rings of the original to the aftermarket reveals the OEM are very robust compared to aftermarket. The aftermarket are very thin and have very little outward tension. So I kept the original piston and rings (barely past break in, if at all).
- Valve springs were already 18lb but I got 22. The nuts on the rockers were so tight that one of the studs broke trying to get them off. So now I have ordered a Champ rocker set that come with bolts. Ugh.
- Upon torquing the head bolts, 2 of them would not torque - just kept going. So I thought I was probably stripping the block but when I pulled them out, they were stretching and were probably close to breaking. Crazy. The torque spec is only 17ft lb.

I thought this would be a couple hours of build time. The billet rod and 275 cam are in. I had to go out and get a 1/4" 12 point socket because I had every socket in the known universe except that one. ARC couldn't just use hex?! Flywheel was easy. No issues there. Gotta get my hardened head bolts and rocker set and then finish it up.

This thing had better kick some a$$.

You most likely got the "thin" ring set.. Theyre supposed to be lower friction.

 

[Edwin Spangler]

Here's the "thin" ring set for comparison.

 

[Hellion]

You should buy one of those Lifan motorcycle engines and make a shifter kart. At least starting off they make 15-20 hp.

 

[Wicked_Daddy]

Here's the "thin" ring set for comparison.

Yep, that's them. And the oil ring set was a PITA. The distribution ring came with a bent edge in it and it was so flimsy, I just couldn't be confident in it.

 

[Wicked_Daddy]

Been super busy with work, then the local freeze/ice storm and then busy again. But finally got around to finishing the Lifan build with all its little challenges that kept delaying things.

Aluminum Flywheel - 28 degrees advance
Billet Rod
Flattop Piston - Cerakoted
Ported and polished the head
.265 cam
Champion Rockers
26 Lb Springs
Nibbi 24mm carb
Racing CC

The CVT would not work with the frame and engine proximity to axle bearing mount. Oh well. Just have to mount this and run it. Maybe this weekend.

 

[Hellion]

Certainly a very clean build. All it needs now is a cherry decal

I was re-reading your misgivings about this engine so there's always the option of getting a Ghost as well. I guess that means another platform (kart or minibike) for it but I am certain it would be a neat comparison between the two engines.

The CVT would not work with the frame and engine proximity to axle bearing mount. Oh well. Just have to mount this and run it. Maybe this weekend.

Well that's a bummer. I'd look for a rear engine kart to go with this engine and a TC/CVT.

 

[panchothedog]

If your gear ratio allows the engine to get into the upper rpm range, I think you'll be pleasantly surprised. From the parts you listed, it should be strong. Most all aftermarket pistons come with rings as shown in post # 29. They work fine. Too.bad yours were bent.

 

[Wicked_Daddy]

Well that's a bummer. I'd look for a rear engine kart to go with this engine and a TC/CVT.

This one turned out to be a good build, even if a little frustrating. The Lifan posed some challenges with some odd sized threads that did not match other aftermarket items made for "clones". But that is what taps are for. Then there were the head bolts that stretched - must be really cheap metal. Those got replaced with higher grade bolts. The piston ring situation was a PITA and I wanted that piston to work. So I took it to a machinist friend that I have done some engine work for and he milled the ring slots to hold the thicker, deeper rings. The originals were barely ran so they got installed. He also Cerakoted the top and skirts. Pretty happy about that. After all is done, I'm excited to run this bad boy.

Meanwhile, I took the advice of this group and bought a stock engine - a 212 Ducar. I have ordered the full array of hi-po parts to make it a screamer. The Ghost was an option but I realized I would end up taking it all apart anyway so why spend the extra to throw away most of the internals anyway. The Ducar was $125 cheaper and comes with a PVL flywheel and the block has cast-in reinforcement that Predators don't have. This one is going to get the full treatment.

And I'm shopping for a frame or kart in need of love on craigslist. Although, there have been some cheap mini-bike frames that make me curious to try that. We'll see. I'm trying to stick with a plan to have 2 karts so that races can happen. The next one will get a CVT, even if I have cut up and re-weld the frame.

 

[Wicked_Daddy]

If your gear ratio allows the engine to get into the upper rpm range, I think you'll be pleasantly surprised. From the parts you listed, it should be strong. Most all aftermarket pistons come with rings as shown in post # 29. They work fine. Too.bad yours were bent.

See my post above - ring problem solved. I like them thick and tight.

The current gear ratio is 3.3:1 so top speed is good even before the engine mods. Should be much better now. It's the low end I want to get better at. Before the mods, it was slow to accelerate out of tight turns or at the slower end of a drift. I want to fix that and will probably decrease the drive sprocket to 12 teeth to see what happens. That would provide 4.9:1 ratio and will sacrifice some top end but with the new engine mods, the top end may end up where it was prior. I'm fine with the that.

 

[panchothedog]

Lowering the gear ratio is exactly what you want. 3.3-1 is way too high. The extra horsepower comes in at the higher rpm range. Seems like you have it figured out.
Good luck with the Ducar build. Great choice.

 

[Wicked_Daddy]

Probably can close out this thread with the installation and test. Finally got around to mounting the Lifan motor (196cc) and tuning the carb to perfection. It screams. And with the gear ratio now at 4.9 (12 tooth CC - 59 tooth sprocket), the acceleration through turn exits and launch from a standstill is impressive. Top speed is 53 MPH. At 1.5 inches off the pavement, it's hair-on-fire fun.

The Ducar 212 will be done within a week or so. Not sure how I will gear that one yet. I may want to go for top speed and keep the Lifan for sport.

 

[Edwin Spangler]

Probably can close out this thread with the installation and test. Finally got around to mounting the Lifan motor (196cc) and tuning the carb to perfection. It screams. And with the gear ratio now at 4.9 (12 tooth CC - 59 tooth sprocket), the acceleration through turn exits and launch from a standstill is impressive. Top speed is 53 MPH. At 1.5 inches off the pavement, it's hair-on-fire fun.

The Ducar 212 will be done within a week or so. Not sure how I will gear that one yet. I may want to go for top speed and keep the Lifan for sport.

Good to hear and looks awesome!

Edit: Dont close it till you add a bunch more pictures!!

 

[Wicked_Daddy]

I need to get a go-pro so I can video driving it. I'm also going to paint the Ducar orange to match the frame. More pics then.