least expensive bicycle engine modification for performance

GoldenMotor.com

Norman

LORD VADER Moderator
Jan 16, 2008
2,606
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pampa texas
Re: least expensive engine modification for performance

You can roll your own pipe if you have a welder not near as pretty as a factory made one but for me it was fun.
 

Norman

LORD VADER Moderator
Jan 16, 2008
2,606
7
38
72
pampa texas
Re: least expensive engine modification for performance

This homemade pipe has the muffler built over the end just a can over the stinger and a1/2" hole with little tail pipe sticking straight down.
 

Norman

LORD VADER Moderator
Jan 16, 2008
2,606
7
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72
pampa texas
Re: least expensive engine modification for performance

I just couldn't resist you need a helmet if you feel the need for speed. Please be kind as my feeling get hurt easly.rotflrotfl
 

paul

Well-Known Member
Dec 23, 2007
5,547
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Kalamazoo, MI
Re: least expensive engine modification for performance

great pictures norman nice job. i need me a helmit like that beer and chips the coneheads lolrotfl
 

Easy Rider

Santa Cruz Scooter Works
Jan 15, 2008
2,145
7
38
Nor*Cal
Re: least expensive engine modification for performance

A expansion chamber will give you the best gains on low, mid and top end but the cheapest would have to be sprocket change. Depending if you're looking for either more low or top end but not both.
I'm digging the helmet Norm! (^)





 
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Norman

LORD VADER Moderator
Jan 16, 2008
2,606
7
38
72
pampa texas
Re: least expensive engine modification for performance

I'm playing with making custom silencers for the pipes you guys are putting on your bike let me know sizes I'll see what me and the Kat can come up with Rufus is getting a little white and needs a good petting.I relly like the pipe but I'l bet it wasn't cheap.
norman
 

HARDKNOCK

New Member
Jan 25, 2008
13
0
0
Jacksonville Florida
Re: least expensive engine modification for performance

I replaced my spark plug wire and wow what a difference in starting and the idling smoothed out too. For those who don't know, its as easy and unscrewing the wire out of the cap and CDI box. Cut a new piece and screw it back in. I used a piece of a VW Hi Performance Silicone wire and I am glad I made the change. I can no longer kill the engine with the choke, guess I will have to hook up the kill switch now!
 

Andyinchville1

Manufacturer/Dealer
Dec 26, 2007
502
1
18
Scottsville, VA
Re: least expensive engine modification for performance

Wow....that must be a drastically better spark.....I guess I'll have to try that!

Thanks for the info.

Andrew
 

Autocycler

New Member
Feb 14, 2008
153
2
0
Metro Washington, DC
Re: least expensive engine modification for performance

I replaced my spark plug wire and wow what a difference in starting and the idling smoothed out too. For those who don't know, its as easy and unscrewing the wire out of the cap and CDI box. Cut a new piece and screw it back in. I used a piece of a VW Hi Performance Silicone wire and I am glad I made the change. I can no longer kill the engine with the choke, guess I will have to hook up the kill switch now!
Cool!!! I thought changing the plug wire would be more complicated...thanks for spelling it out for us.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
Re: least expensive engine modification for performance

I replaced my spark plug wire and wow what a difference in starting and the idling smoothed out too. For those who don't know, its as easy and unscrewing the wire out of the cap and CDI box. Cut a new piece and screw it back in. I used a piece of a VW Hi Performance Silicone wire and I am glad I made the change. I can no longer kill the engine with the choke, guess I will have to hook up the kill switch now!

What wire size did you use?
 

Autocycler

New Member
Feb 14, 2008
153
2
0
Metro Washington, DC
Re: least expensive engine modification for performance

Hi Cruiser,

I received the plug wire yesterday and it does make a big difference in the overall performance of my bike. My immediate impression was how easily the bike started (temperature in the teens this morning). The engine idles a bit more smoothly also. This is an easy and helpful upgrade!
Thanks so much!
 

Enerarevir

New Member
Oct 2, 2008
13
0
0
Re: least expensive engine modification for performance

Those of you that might have read any previous post of mine will know that I'm "new to all this about motorized bicycles and have yet to do my first build (I'm waiting to move to Puerto Rico to do mine). But after reading in this thread, I've found that I DO have some experience that will probably help on doewn the road. Years ago I had a Puch moped (I loved it). Since I had to register it in Puerto Rico, I decided that I might as well improve performance. What I did was: alter jet size, eliminate original head gasket after "glass finishing" head and cylinder surfaces, boring a few holes in exhaust (but then extended it with a fiberglass packed pipe, and installing a smaller rear sprocket that I took off an old mini dirt bike.

Well, the end result was that my former top speed of about 28 MPH went up to close to 40 MPH. So, I guess, after reading this post, I've confirmed that my reasoning was sound. Mind you, I had nobody to ask advice of and all this was done as an experiment born of the fact that I had I moped that I had had to register as a "motorcycle".
 

mechanickid

New Member
Aug 7, 2008
419
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0
nh
"Another easy mod is remove the sparkplug and using a dremel cut the ground electrode to a v shape this uncovers the electrodes so the flame curnel is exposed better to the fuel mixture which permits better combustion of the fuel."

what is a ground electrode?

could i make a boost bottle out of a large sealed soda can? how do i hook it up?

doesn't the exhaust need a little resistance? i hear its bad for the motor if its just running into thin air.

would ngk snowmobile spark plug wire be a good upgrade? i've got the best kind :p

thanks guys
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
"Another easy mod is remove the sparkplug and using a dremel cut the ground electrode to a v shape this uncovers the electrodes so the flame curnel is exposed better to the fuel mixture which permits better combustion of the fuel."

That is a disaster waiting to happen...if you bend the electrode out enough on a plug to "dremel a V groove" and bend it back to gap it, you may as well just break it off, throw it in the spark plug hole and try to start your engine!
That's not going to improve the performance of these engines one bit.


what is a ground electrode?

The part of your plug you don't want to bend back and forth.

could i make a boost bottle out of a large sealed soda can? how do i hook it up?
Boost bottles have to be rigid. They only help if they are perfectly set up, your carb is perfectly set up, and then it has been the experience of many her ethat they are a waste of time and money.

doesn't the exhaust need a little resistance? i hear its bad for the motor if its just running into thin air.

They don't NEED backpressure, but without it, they don't like to run at anything other than wide open and very rich.
would ngk snowmobile spark plug wire be a good upgrade? i've got the best kind :p

Definitely.

thanks guys

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