Honda GX 160 ?
- Thread starter MICHAEL JOE
- Start date
Who knows? Probably not enough power and RPM to make you happy.
Pull the head and have a look at the cylinder. If it looks good then build it for more power and safe high RPM operation. Rod and flywheel are the parts you need to run with ungoverned.
Recently watched a video with a GX160. The guy had a mikuni, cam, and PVL flywheel running ungoverned. Too bad he didn't get a billet rod because he ended up breaking the stock rod.
GX160... Very cool. Don't increase the chances of ruining it with governor removal without the parts to support high RPM operation.
Pull the head and have a look at the cylinder. If it looks good then build it for more power and safe high RPM operation. Rod and flywheel are the parts you need to run with ungoverned.
Recently watched a video with a GX160. The guy had a mikuni, cam, and PVL flywheel running ungoverned. Too bad he didn't get a billet rod because he ended up breaking the stock rod.
GX160... Very cool. Don't increase the chances of ruining it with governor removal without the parts to support high RPM operation.
The gx160 stock rod is the same rod used in the gx200 and clone 196, 3.303" stock length.
Theres different wrist pin heights when choosing rod piston combos for the 160 and 200/196.
I find it best to measure piston to deck, then chose the rod length to get the piston as close as possible to deck, but not out of it. Then choose a head gasket that will get you close to .030" piston to deck.
There's a light weight flat top piston, and +.080" billet rod combo for the 160.
The 160 needs all the help it can get, lightweight parts don't cost much more then regular parts.
A 160 with .030" piston to deck (head gasket included), flat top piston, and the stock 14cc head will have 10.7:1 CR. This will pull much harder then stock in the entire rpm range.
With a dished piston, will have 9.1: CR. Thats not much more the stock, and IMHO wouldn't be worth building, or adding billet parts to.
This piston with the 6770 rod would be my 1st choice when building a gx160.
https://www.arcracing.com/dj-2195-std-honda-gx160-gx200-t2-piston/
Theres different wrist pin heights when choosing rod piston combos for the 160 and 200/196.
I find it best to measure piston to deck, then chose the rod length to get the piston as close as possible to deck, but not out of it. Then choose a head gasket that will get you close to .030" piston to deck.
There's a light weight flat top piston, and +.080" billet rod combo for the 160.
The 160 needs all the help it can get, lightweight parts don't cost much more then regular parts.
A 160 with .030" piston to deck (head gasket included), flat top piston, and the stock 14cc head will have 10.7:1 CR. This will pull much harder then stock in the entire rpm range.
With a dished piston, will have 9.1: CR. Thats not much more the stock, and IMHO wouldn't be worth building, or adding billet parts to.
This piston with the 6770 rod would be my 1st choice when building a gx160.
https://www.arcracing.com/dj-2195-std-honda-gx160-gx200-t2-piston/
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So I'm just doing some math here, (because I also have a couple gx160s in the corner)...
At a minimum, ungoverning for power and safety will cost roughly $270 to $420.
Aluminum flywheel $60
(Optional Billet flywheel $180)
Billet rod $85
Flat top piston + rings $35
Open header $40
Air filter, stack & choke lever (kit) $35
Throttle control assembly - basic $15
(Optional throttle top plate $45)
And that's not even counting the carb jetting!
And then there's all the valve train options!
Ugh, and ouch.
Kinda makes ya wanna just loosen the stock throttle handle and install as-is. I mean, shouldn't 5.5hp be good enough for most kids?
At a minimum, ungoverning for power and safety will cost roughly $270 to $420.
Aluminum flywheel $60
(Optional Billet flywheel $180)
Billet rod $85
Flat top piston + rings $35
Open header $40
Air filter, stack & choke lever (kit) $35
Throttle control assembly - basic $15
(Optional throttle top plate $45)
And that's not even counting the carb jetting!
And then there's all the valve train options!
Ugh, and ouch.
Kinda makes ya wanna just loosen the stock throttle handle and install as-is. I mean, shouldn't 5.5hp be good enough for most kids?
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Thanks BrownStainRacing,
I went ahead and dug your "recipe" out of the post above. This is awesome stuff:
BrownStainRacing says:
Leave gov in it, use a NEW stock rod in it,
Shim crank and cam to .010"-.012"
Use a ft piston
Cast aluminum flywheel
Set ignition timing to 28*
Coil air gap at .045"
Head gasket to get .030" piston to deck
Use a bored SA carb .625" or bigger.
Use a isky black mamba jr cam with 26# springs at .840" installed height.
Open up the bowl areas in the head.
Unshround valves
The rest of the valve train stock.
A good header and better air box
Set governor to 5300 rpm
It'll be closer to 10hp then it will 5.5.
I went ahead and dug your "recipe" out of the post above. This is awesome stuff:
BrownStainRacing says:
Leave gov in it, use a NEW stock rod in it,
Shim crank and cam to .010"-.012"
Use a ft piston
Cast aluminum flywheel
Set ignition timing to 28*
Coil air gap at .045"
Head gasket to get .030" piston to deck
Use a bored SA carb .625" or bigger.
Use a isky black mamba jr cam with 26# springs at .840" installed height.
Open up the bowl areas in the head.
Unshround valves
The rest of the valve train stock.
A good header and better air box
Set governor to 5300 rpm
It'll be closer to 10hp then it will 5.5.
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Isky small cams that close the intake valve early.
Get CR up as close to 10.5:1 as you can and the BMJ never fails for fun time cruising, beating the trails, you know the good ol fun stuff we could do when we was younger.
The CL1 cam or any other stock lift cam works good with 22# springs and 1.3:1 stamped steel rockers, as long as you get the CR up.
Theres a night and day difference the way these lil turd motors will run, when you can squeeze that air/fuel mix harder. It really wakes em up. Even with a stock .580"-.590" carb.
But get that intake valve to close while the piston is further down in the cylinder will definitely pick up the torque in the same rpm range, gov'ed or no gov.
Get CR up as close to 10.5:1 as you can and the BMJ never fails for fun time cruising, beating the trails, you know the good ol fun stuff we could do when we was younger.
The CL1 cam or any other stock lift cam works good with 22# springs and 1.3:1 stamped steel rockers, as long as you get the CR up.
Theres a night and day difference the way these lil turd motors will run, when you can squeeze that air/fuel mix harder. It really wakes em up. Even with a stock .580"-.590" carb.
But get that intake valve to close while the piston is further down in the cylinder will definitely pick up the torque in the same rpm range, gov'ed or no gov.
