What should I install next?

[Chris7420]

Just want to show you guys my bike and looking for some advice on what to install next, so far I’ve installed a kinbelle fat belly pipe and I cut the muffler off my original exhaust and fitted it to the end, I also enlarged the hole on the cap. I installed a high compression head as well and set the squish to 0.030” and I have a sbp air filter. I haven’t installed it yet but I also ordered a 36t sprocket, currently I have a 44t. Also wondering what you guys think of my spark plug colour, is it rich or lean? Im running whatever jet it came with and the needle is set at the highest position cause that seems to be where it runs best and 4 strokes the least. I use champion 306 spark plugs cause they never have the ngk ones in stock I believe the champion 306 is the same as ngk br6s though. My bike goes about 45-50 km/h but at 50 the motor is pretty revved up, I want it to be able to go 50 easily so I can keep up with traffic without reviving the motor out to much. Links below to all the parts I used.

Air Filter - Low Profile Chrome

Motorized bicycle, motor bike, electric bike, ebike, pedal assist

sickbikeparts.com

https://www.amazon.ca/gp/aw/d/B07ZPMTX47?psc=1&ref=ppx_pop_mob_b_asin_title

66cc / 80cc High Performance Head

Compatible with GT5, GT5AWoody WoodPecker's High Performance / High Compression run cool head.Brushed aluminum finish. 6cc combustion chamber; Means high compression. It Fits 66cc and 69cc engines using M8 head bolts and 47mm dia. pistons. Extra cooling fins and extra mass means better engine...

motorizedbicycle.ca

 

[Chris7420]

 

[wrench]

Install a head light and tail/stop light on your M/B.
Just like a M/C or Moped your M/B should have lights.
Besides then you can have fun riding at night too.

 

[Tyler6357]

The 36 tooth sprocket should give you more speed. You could put a reed valve on if you want more power or you could put a shift kit on it and take advantage of your gears. You could get a dual leg kick stand (center kickstand), you could get a dual brake lever, you could get a shock fork and update to disc brakes. A sprocket adapter would be a good upgrade too.

 

[Tyler6357]

That plug looks ok, maybe a little on the lean side.

 

[Chris7420]

The 36 tooth sprocket should give you more speed. You could put a reed valve on if you want more power or you could put a shift kit on it and take advantage of your gears. You could get a dual leg kick stand (center kickstand), you could get a dual brake lever, you could get a shock fork and update to disc brakes. A sprocket adapter would be a good upgrade too.

Ive thought about installing a reed valve but I’ve read a lot of bad reviews on reed valves of people saying they installed one and it made they’re bike slower, I even saw a video of a guy who dyno’d an engine before and after installing a reed valve and it made like half as much power.

 

[Chris7420]

Yeah here’s the video I mentioned, there’s another one where they install the reed valve as well as window piston and it still makes less power then stock. Do you need to change something else to make it work? Or did they just have a no good reed valve?

 

[Tyler6357]

Yeah here’s the video I mentioned, there’s another one where they install the reed valve as well as window piston and it still makes less power then stock. Do you need to change something else to make it work? Or did they just have a no good reed valve?

Wow, I don't know what to say about this. I didn't have any trouble with mine and it definitely gave me more power and higher top end. But I should say that mine is the 4 peddle type, also, I'm not using an NT carb, I'm running a VM18 Mikuni carburetor which I'm certain had an effect. Here is a pic

 

[Tyler6357]

This is the reed valve that I got:

Pro 2 in1 Racing Reed Valve for 32/40mm Intake 66/80CC Gas Motorized Bicycle | eBay

The Racing Reed Valve Kit -Suitable for 40mm and 32mm Intake - 2 in1 - 66CC/80CC Gas Motorized Bicycle；. Good apply on regular 32mm or 40mm intake cylinder directly. 1 x Reed Valve Kit. It Valve Works Well On Normal Piston and Cylinder,Better performance if works with windowed piston.

www.ebay.com

They don't really show you the 4 peddles but they look just like this:

CDHPOWER G2 Racing Reed Valve Kit Block Only - Gas Motorized Bicycle 66cc/80cc | eBay

Reed Block for G-2 reed valve;.

www.ebay.com

I also got a windowed piston similar to this:

Motorized bicycle 47mm REED VALVE READY Window Piston for 47mm Cylinder | eBay

Find many great new & used options and get the best deals for Motorized bicycle 47mm REED VALVE READY Window Piston for 47mm Cylinder at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I also got one of these larger intakes for it to fit my Mikuni vm18 carb.

CDHPOWER G2 Reed Valve CNC Intake 19mm/21mm/23mm of CDHPOWER G2 Reed Valve Kit | eBay

CDHpower G2 Reed Intake of CDHpower G2 Reed Valve Kit -19mm. CDHpower G2 Reed Intake of CDHpower G2 Reed Valve Kit -21mm. CDHpower G2 Reed Intake of CDHpower G2 Reed Valve Kit -23mm. CDHpower G2 Reed Valve cnc Intake.

www.ebay.com

 

[Tyler6357]

I should also say that my engine is a PK80 with the short connecting rod and the low wrist pin type piston. That windowed piston might not work with your engine if you use a different type of piston.

 

[Tyler6357]

Also, another good upgrade for that bike is some good road tires. It looks like you have pretty fat rims, you could probably get wider tires which means better traction and the ability to lean into turns more. It's worth it to spend extra cash on tires and get good ones. MBs can run through cheap tires fast, at least the rear one with the engine drive on it.

 

[Chris7420]

Also, another good upgrade for that bike is some good road tires. It looks like you have pretty fat rims, you could probably get wider tires which means better traction and the ability to lean into turns more. It's worth it to spend extra cash on tires and get good ones. MBs can run through cheap tires fast, at least the rear one with the engine drive on it.

Yeah I definitely want to get some better wheels/tires. I’ve bent 2 back rims hitting jumps and stuff already thankfully I have a bunch of extras

 

[Chris7420]

This is the reed valve that I got:

Pro 2 in1 Racing Reed Valve for 32/40mm Intake 66/80CC Gas Motorized Bicycle | eBay

The Racing Reed Valve Kit -Suitable for 40mm and 32mm Intake - 2 in1 - 66CC/80CC Gas Motorized Bicycle；. Good apply on regular 32mm or 40mm intake cylinder directly. 1 x Reed Valve Kit. It Valve Works Well On Normal Piston and Cylinder,Better performance if works with windowed piston.

www.ebay.com

They don't really show you the 4 peddles but they look just like this:

CDHPOWER G2 Racing Reed Valve Kit Block Only - Gas Motorized Bicycle 66cc/80cc | eBay

Reed Block for G-2 reed valve;.

www.ebay.com

I also got a windowed piston similar to this:

Motorized bicycle 47mm REED VALVE READY Window Piston for 47mm Cylinder | eBay

Find many great new & used options and get the best deals for Motorized bicycle 47mm REED VALVE READY Window Piston for 47mm Cylinder at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I also got one of these larger intakes for it to fit my Mikuni vm18 carb.

CDHPOWER G2 Reed Valve CNC Intake 19mm/21mm/23mm of CDHPOWER G2 Reed Valve Kit | eBay

CDHpower G2 Reed Intake of CDHpower G2 Reed Valve Kit -19mm. CDHpower G2 Reed Intake of CDHpower G2 Reed Valve Kit -21mm. CDHpower G2 Reed Intake of CDHpower G2 Reed Valve Kit -23mm. CDHpower G2 Reed Valve cnc Intake.

www.ebay.com

What do you think of this - https://www.ebay.com/itm/133650408857?hash=item1f1e2f6599:g:4H0AAOSwVSpdn8Ow
Also I’m worried it won’t clear the frame on my bike, what do you think? There’s photos of my bike in the first post on this thread

 

[Tyler6357]

What do you think of this - https://www.ebay.com/itm/133650408857?hash=item1f1e2f6599:g:4H0AAOSwVSpdn8Ow
Also I’m worried it won’t clear the frame on my bike, what do you think? There’s photos of my bike in the first post on this thread

It will clear the frame fine because the reed valve intake is angled away from the frame so it will stick out of the side of the bike. I don't know much about the rest of it. It's great to port your cylinder, if it's done correctly, most of us do it ourselves with a Dremel tool. I can't say anything about that carb or how good it is because I've never tried those kind. Looks like they have pieced it together with a hose and clamps. Meh, overall I would say that it seems kinda expensive for what you get but everything seems more expensive these days.

 

[Tyler6357]

Yeah I definitely want to get some better wheels/tires. I’ve bent 2 back rims hitting jumps and stuff already thankfully I have a bunch of extras

I can't see exactly which wheels you got on there. Wider rims are best. If you are going to the trouble of changing the wheels, then you might as well go for a disc brake hub on the back, that way you can hook the rear sprocket into the disc brake hub and get rid of the stock rag joint set up that drives the spokes. I've got a 36 tooth sprocket on it. Pic #1

However, it might be difficult to find one like that with gears. Also, those that you have on right now don't look that bad at all. What size tires do you have on it right now? You can get a sprocket adapter for geared hubs like yours. I used to have gears on my bike and I was using a sprocket adapter. I think it's much better to drive the hub instead of the spokes. Pic #2

 

[Tyler6357]

If you decide to get one, I recommend that you get one of these 3 bolt types. I got mine years ago before these were widely available. They will fit the 1.5 or 1 inch diameter hubs because they come with a shim that you can put in to work on the smaller hubs like the geared ones.

For 80cc Motorized Bicycle 1" (25mm) / 1.5" (38mm) CNC Adapter Sprocket 32T-44T | eBay

Find many great new & used options and get the best deals for For 80cc Motorized Bicycle 1" (25mm) / 1.5" (38mm) CNC Adapter Sprocket 32T-44T at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[Chris7420]

If you decide to get one, I recommend that you get one of these 3 bolt types. I got mine years ago before these were widely available. They will fit the 1.5 or 1 inch diameter hubs because they come with a shim that you can put in to work on the smaller hubs like the geared ones.

Thanks so much for all the info/advice. I’m thinking now I might just leave this bike as is and get a nicer bike and one of these kits and build it up. Have you seen these yet? I’ve read a lot of good review apparently they’re monsters - https://www.bicycle-engines.com/ztm...engine-kit-true-85cc-bike-motor-36t-sprocket/

 

[Chris7420]

Oh and the wheels on my current bike are 26x1.95

 

[Tyler6357]

Oh and the wheels on my current bike are 26x1.95

Looking at the width of your rims, it looks like you could go up to 26x2.015 or maybe even 26x2.25 or possibly even 2.35's will fit, I really can't see it in the picture that well, but at least up to 26x2.00s. Just make sure you have chain clearance so the chain don't hit the tire. If you get the sprocket adapter it will move the rear sprocket away from the wheel a little more than the rag joint set up.

 

[Tyler6357]

Wow, 52mm bore, that's got to be pretty fast. That's something new, don't know how good they are but it's got to have more torque than standard China girls. But to be honest, my bike goes fast enough, I can hit 50+ mph if I really wind it up, but really, I don't need to go that fast on a bicycle.