HS 4G: Maximum performance....

GoldenMotor.com
hrichmon@gmail.com

[email protected]

New Member
Sep 25, 2009
117
0
0
San Diego
Hey guys,

I’ve built a few of these now, and am wondering if anyone has crossed any methods/secrets to maximize the performance of these kits. (like changing the spark plug on a 2 stroke). I’m very happy with the way they run, but I wonder if they “can” run better....
 
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
Hunter you can port the intake and exhaust a little and you can put a low flow muffler on it and the same for the air filter you could even have you crank and piston balanced. For now that is about it, I have been searching and searching for performance part and as yet they do not exists. If you want real power from a 4 stroker then we have to get a performance cam to start and there is no such thing, the cams are made of plastic every thing has to start from there then clean up the flow in the head. once that is done you would see greatly improved performance. I am sure there are people that will argue the cam thing but that is where I always start for real performance increase.
 
Bikeguy Joe

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
Raising the compression is free hp. Easily done on a flat head, not too hard on an OHV.

Open up the exhaust and intake (even if it's just the muffler and air box) and re set/re-jet the carb accordingly.
 
Bikeguy Joe

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
Plastic cam? Crazy, and sad.

But wait! If it's plastic, it should be easy to re-grind like the old timers did before you could throw a credit card at an engine to make it perform better.
 
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
I would not do anything to the cam because you have to know exactly what you are doing. Anything done with the cam should be backed up with dyno results it is not as simple as shaving something off the cam. Now if you want true performance results you will do the following things
1. Have your crank and piston balanced
2. Have your cylinder head shaved this will increase you compression
3. Port your intake and exhaust
4. Match your gaskets to your head and intake and the same for the exhaust
5. Put on a high flow exhaust
6. Put on a hight flow air filter
7. Install the very best spark plug you can find for your engine and have it gapped properly
now if you do the things 1. though 7. you will see a significant improvement or get your hands on a Super Titan this is the same engine with increased compression
 
tyrslider

tyrslider

New Member
Sep 26, 2008
958
2
0
RainCity
Hey you guys,

The Honda and HS have an integrated cylinder and head. As in the head and cylinder are attached as one piece cast into the top half of the case which is split diagonally.

49cc 4-Stroke Engine Parts Diagram

No milling the head is possible. It is possible (if someone makes'em) to put a higher compression piston and rings. Joe, Wiseco?

You do not want to grind the cam; you want a high lift cam (good luck). If you could open the valves more (high lift cam) you'd need stronger springs. Plastic cam not gonna like a that!

You want a high flow airfilter and high flow exhaust; it is an air pump more air and more exhaust = more power (which is why you want a high lift cam) more, more, more. More air, more gas, more compression for higher octane, cooler, cleaner burning gas and alas more power.

These are not performance motors. But more air and more exhaust (which should include rejetting the carb i.e. more gas) is doable.

For the sake of common language and understanding, porting is something you do to 2 stroke cylinders. On four strokes you flow the heads and intake. Theres more to it than smoothing them out but even just smoothing them out is helpful and it's called flowing the heads.

Cheers! Evan

Ride it hard and put it away wet!
 
Last edited:
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
Thank you Evan did not know that about the cylinder so you can't even touch the head and have it milled??? I have been looking for jets for the carb I can not find any at all. But you can port match any four stroke as well some people can that blue printing. Plus any thing you do to the head will help. Now I was always told that flowing heads was for multi cylinders and making sure the flow rate is the same for each cylinder. Same for cc ing the heads that is the matching of fluid contained in each head chamber of which is not necessary on single cylinder so if if you really want to be technical all you can do is clean up the flow not match it. Do you know Evan where to get the jets from ??? and thank you once again Evan you are the master. Glad to hear you are ready to start adding your new products to your website.

Terry
 
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
Evan I have one more question I am trying to find a 56 tooth sproket for my new build and it has a Grubee HD Axle Kit with a Free wheel can you make me a 56 tooth sprocket for that??? If you need I can send you the 48 tooth I have so you can match the holes
Thank you
Terry
 
tyrslider

tyrslider

New Member
Sep 26, 2008
958
2
0
RainCity
Right On Terry,

I may not be entirely accurate either, linguistically, but 2 smokes have ports that can be raised, lowered, widened etc. i.e. porting. 4 strokes have intake and ehaust ports that are typically a rough cast surface and can be smoothed out and shaped in a way that allows air to flow through easier i.e. flow. Both have ports and both benefit from better flow.

You make good points.

I guess I am seeing that people are now referring to any smoothing out or matching of anything to be porting (lack of adjectives, that's all).

It's All Good! Cheers!

Cheers!
 
jared8783

jared8783

New Member
May 13, 2009
216
0
0
Elkhart, IN
Terry Blow said:
Here is a picture of the cam for any who cares

View attachment 25357
Click to expand...
Hey Terry where did you get those pics from I would like to see more.

And is there another lobe on the other side of the cam?
I dont understand how one lobe will control 2 valves

Wait a minute, each lobe in my car controls 2 valves, but then again its a VW and I just dont see how one lobe can do the trick in these engines.
 
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
Hi there my guess would be that there is another lobe on the other side BUT I have seen engine with single lobe per cylinder in several engines including early Jeeps. And even more engines with single lobe cams in aircraft engines. I highly doubt this is one of those engines. Here is a link to all the engine parts and and exploded view and list of parts and names from bicycle-engines.com 49cc Engine Parts
 
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
I just remembered the name of the engine company that put single lobe cam engines in Jeeps was called Kaiser they also build aircraft engines
 
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
Here is a cut and past from the internet
Jeep Tornado engine - Wikipedia, the free encyclopedia
It was the only U.S.-built overhead-cam engine in production at that time. ... One lobe operated both the intake and exhaust valve for each cylinder. ... 1966–82; Industrias Kaiser Argentina (IKA) produced Jeep vehicles from 1956–78 ...
 
Terry Blow

Terry Blow

Dealer & Custom Builder
Oct 29, 2009
1,117
3
0
Surrey B.C Canada
LOL it is a cool design the valves are in a Vee pointing away from each other and with the engineers doing some incredible math there you have it single lobe per cylinder and there where thousands of them made I will see if I can find any thing more if you research more you will find out that even Harley Davidson used them
 
You must log in or register to reply here.
Top Bottom