Pocket Bike Engine Project II
- Thread starter lowracer
- Start date
Here are a few pics & eBay description of the Stage7 kit I bought to repair my blown engine. The sellers English isn't great but as long as the kit is I'll be happy. Sure looks & sounds like the cylinder is polished...
1. Alloy Cylinder Head : 1Piece. SILVER COLOR.
2. Most Performance Cylinder for Racing: 1Piece. WE ARE ORIGINAL!!! The Cylinder Contain Improved Big and Deep Transfer Port By CNC and Much Bigger Exhaust Port Inside and Outside By Hand And Not So Easy To do. Therefore It is The Highest Compression Available At Present-Only We Have!!! And Our Cylinder is So Much Clean Looking. Remember This: No Other Sellers are Willing To Spend So Much Time and Energy Doing Such Most Performance Cylinder Like US!!!
3. Performance Piston Kit: Including 1 Piston 44MM, 1 Pin 12mm, 2 Clips and 1 Quality Needle Bearing.
4. Quality Piston Rings: 2 Sets. Only We Sell Like That!!!
5. Gaskets: 2 Sets. One Set is Complete Gaskets With Copper Head Gasket (6PCS). The Other Set is Complete Paper Gaskets With Paper Head Gasket (6PCS). Only We Sell Like That!!
6. HP Crank: 1PC For 12MM Piston Pin. ONLY We Have Top Quality and Smooth HP Crank!!! Others are All Dirty , Not Smooth
7. HP Carbon Reed: 1Piece. It Can Help Your Bike to Get More Power!!!
1). Top Quality and Very Shining Rocket Key: 1Piece. Only We Have Such Shining and Smooth Rocket Key!!! If You Want to Get the Most Power from Your Bike, Our Timing Advance Key is A Must!!!
2). Quality Spark Plug: 1Piece.
3). Copper Rings for Cylinder Head: 2PCS.
4). Much Stronger Long Screws for Racing Cylinder: 4PCS.
1. Alloy Cylinder Head : 1Piece. SILVER COLOR.
2. Most Performance Cylinder for Racing: 1Piece. WE ARE ORIGINAL!!! The Cylinder Contain Improved Big and Deep Transfer Port By CNC and Much Bigger Exhaust Port Inside and Outside By Hand And Not So Easy To do. Therefore It is The Highest Compression Available At Present-Only We Have!!! And Our Cylinder is So Much Clean Looking. Remember This: No Other Sellers are Willing To Spend So Much Time and Energy Doing Such Most Performance Cylinder Like US!!!
3. Performance Piston Kit: Including 1 Piston 44MM, 1 Pin 12mm, 2 Clips and 1 Quality Needle Bearing.
4. Quality Piston Rings: 2 Sets. Only We Sell Like That!!!
5. Gaskets: 2 Sets. One Set is Complete Gaskets With Copper Head Gasket (6PCS). The Other Set is Complete Paper Gaskets With Paper Head Gasket (6PCS). Only We Sell Like That!!
6. HP Crank: 1PC For 12MM Piston Pin. ONLY We Have Top Quality and Smooth HP Crank!!! Others are All Dirty , Not Smooth
7. HP Carbon Reed: 1Piece. It Can Help Your Bike to Get More Power!!!
1). Top Quality and Very Shining Rocket Key: 1Piece. Only We Have Such Shining and Smooth Rocket Key!!! If You Want to Get the Most Power from Your Bike, Our Timing Advance Key is A Must!!!
2). Quality Spark Plug: 1Piece.
3). Copper Rings for Cylinder Head: 2PCS.
4). Much Stronger Long Screws for Racing Cylinder: 4PCS.
Attachments
In pocket bike forum they claimed that this is the best chinese kit stock aside from the PBU one. I'm jealous now lol.
Looks like this guy:
http://cgi.ebay.com/ebaymotors/Pock...rcycles_Parts_Accessories&hash=item2a146faeb4
Is located in China. Good luck on waiting 3-4 weeks to get it delivered.
You will get more mid/ top end and horsepower. Acceleration may not be as good however because the volume of the ports are larger so the velocity of fuel won't be great in the beginning.
The widened port in the second picture, looks like 3 ports in the first picture if you look on the cylinder in the first picture.
Looks like this guy:
http://cgi.ebay.com/ebaymotors/Pock...rcycles_Parts_Accessories&hash=item2a146faeb4
Is located in China. Good luck on waiting 3-4 weeks to get it delivered.
You will get more mid/ top end and horsepower. Acceleration may not be as good however because the volume of the ports are larger so the velocity of fuel won't be great in the beginning.
The widened port in the second picture, looks like 3 ports in the first picture if you look on the cylinder in the first picture.
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It looks & claims to have hand polished cylinder walls & ports (it is shiny in the pics). Also the head looks better than the stock stage2 head due to the cooling fins. The stock billet alloy head runs hot (I believe) & has none of those cooling fins.
I'll post my impressions once it arrives & I get some mileage on it. If I like it, I'll need to swap it over to 'The Beast'.
-Lowracer-
I'll post my impressions once it arrives & I get some mileage on it. If I like it, I'll need to swap it over to 'The Beast'.
-Lowracer-
My stage 2 is polished on my engine also so that's not really a difference.
The stock 1 piece cylinder does run hot (mines was smoking smoke after rides when I used to own one so I sold it because of that).
The difference is the ports. Ports seem very attractive to my eyes there.
The larger ports may reduce fuel efficiency.
If you have any good impressions and think it's better than the stage 2 when it arrives let me know and I might get one too. Acceleration might not be as good as the stage 2, but top end will be top notch.
But then again the stage 2 is poorly ported, so acceleration may be worse than it should be (some people reported it worse than the stock pocket bike engine 1 piece cylinder kit). And for true power gains people port them on their own depending on what type of power they need (acceleration/ torque, hp, mid/ top end).
The stock 1 piece cylinder does run hot (mines was smoking smoke after rides when I used to own one so I sold it because of that).
The difference is the ports. Ports seem very attractive to my eyes there.
The larger ports may reduce fuel efficiency.
If you have any good impressions and think it's better than the stage 2 when it arrives let me know and I might get one too. Acceleration might not be as good as the stage 2, but top end will be top notch.
But then again the stage 2 is poorly ported, so acceleration may be worse than it should be (some people reported it worse than the stock pocket bike engine 1 piece cylinder kit). And for true power gains people port them on their own depending on what type of power they need (acceleration/ torque, hp, mid/ top end).
I'll let you know what I think of it after putting it through its paces.
I cant see how the stock 2hp cag is anywhere faster than the 4hp Stage 2 kit?
I do know that I am real happy with both my Stage 2 kits that I've been running & love their power, both acceleration & top end.
I finally mounted the rpm meter I recently got to my steerer stem & like having that info right in my face at all times.
-Lowracer-
I cant see how the stock 2hp cag is anywhere faster than the 4hp Stage 2 kit?
I do know that I am real happy with both my Stage 2 kits that I've been running & love their power, both acceleration & top end.
I finally mounted the rpm meter I recently got to my steerer stem & like having that info right in my face at all times.
-Lowracer-
4hp stage 2 might be a hype because the porting is faulty there which might cause it to be worse than the stock (however this may not be true, but that is what some users reported). I wish I had my old engine to compare to to know if the stage 2 kit (with stock porting) really is worse or better than the stock 1 piece cylinder kit. When ported, then it will produce the true power. Porting is fairly easy to do, just need patience.
But then again there is another pocket bike engine builder in this forum and he claimed that his stage 2 runs better and stronger than his stock 1 piece cylinder pocket bike engine that he compared it to. So don't get turned down. I myself would rather not port it because I have no experience with that and will just admit that the stage 2 kit has more power than the stock cylinder kit.
You can read up pocket bike planet if you do not agree, and I am not pro at this so that place can help.
For me I don't mind either and am happy with the stage 2 kit as long as it has a lot of power (which can be hand ported easily to gain more power) because the way the stock cylinder sounds is ridiculous and loud.
By the way, what RPMs have you reached?
But then again there is another pocket bike engine builder in this forum and he claimed that his stage 2 runs better and stronger than his stock 1 piece cylinder pocket bike engine that he compared it to. So don't get turned down. I myself would rather not port it because I have no experience with that and will just admit that the stage 2 kit has more power than the stock cylinder kit.
You can read up pocket bike planet if you do not agree, and I am not pro at this so that place can help.
For me I don't mind either and am happy with the stage 2 kit as long as it has a lot of power (which can be hand ported easily to gain more power) because the way the stock cylinder sounds is ridiculous and loud.
By the way, what RPMs have you reached?
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Gera,
I'm a member of that forum too but dont post (just read alot). I like to try stuff out for myself, compare & contrast. I'm sure you can squeeze more power out of any engine but at what cost? These motors are already overpowered for a traditional bicycle application. A Downhill bike is better suited to this kind of power where you can actually use it more safely. I got one on a 'Regular' bike & one on a 'Downhill' bike & the Stage2 is better suited to the DH bike & way overkill on the Regular bike.
-Lowracer-
I'm a member of that forum too but dont post (just read alot). I like to try stuff out for myself, compare & contrast. I'm sure you can squeeze more power out of any engine but at what cost? These motors are already overpowered for a traditional bicycle application. A Downhill bike is better suited to this kind of power where you can actually use it more safely. I got one on a 'Regular' bike & one on a 'Downhill' bike & the Stage2 is better suited to the DH bike & way overkill on the Regular bike.
-Lowracer-
Gera,
I have hit 11,000 rpm's before. I just took it for a quick blast to verify my memory & hit 10,740 rpm's within about a quarter mile running cold (over 51 mph) on 'The Beast' see my avatar (not the bike this thread was created about).
-Lowracer-
I have hit 11,000 rpm's before. I just took it for a quick blast to verify my memory & hit 10,740 rpm's within about a quarter mile running cold (over 51 mph) on 'The Beast' see my avatar (not the bike this thread was created about).
-Lowracer-
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Gera,
I am tracking the pkg from China & this seller shipped it via DHL Express (4-7 day delivery).
Not too shabby for free shipping...
-Lowracer-
I am tracking the pkg from China & this seller shipped it via DHL Express (4-7 day delivery).
Not too shabby for free shipping...
-Lowracer-
My fastest package from China arrived pretty quick as well. Under 10 days I believe. The shipping was as fast as from Canada at least.
Did you have a rocker key to get advanced timing?
And 51mph... that's a scary speed.
How much speed can I achieve with a 3:1 reduction gearbox and 14tooth front and 72 rear? 15.4:1 ratio
I have a 14 tooth front as stock, but might change it to 11 if I need too.
11 tooth would be 19.6:1 Ratio
Did you have a rocker key to get advanced timing?
And 51mph... that's a scary speed.
How much speed can I achieve with a 3:1 reduction gearbox and 14tooth front and 72 rear? 15.4:1 ratio
I have a 14 tooth front as stock, but might change it to 11 if I need too.
11 tooth would be 19.6:1 Ratio
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55.2 mph using 14 tooth if you too can pull 11,000 rpm's using a 26" diameter tire
43.3 mph using 11 tooth.
What kind of bike are you putting it on?
Most bicycles can't travel 55 mph safely (very high danger & certain destruction).
I am able to go fast using a stable DH MTB (triple clamp fork/20mm thru axle/7" full suspension/Heavy Duty everything).
You may get some friction losses using that 3:1 chinese transmission that I cant account for.
-Lowracer-
43.3 mph using 11 tooth.
What kind of bike are you putting it on?
Most bicycles can't travel 55 mph safely (very high danger & certain destruction).
I am able to go fast using a stable DH MTB (triple clamp fork/20mm thru axle/7" full suspension/Heavy Duty everything).
You may get some friction losses using that 3:1 chinese transmission that I cant account for.
-Lowracer-
As far as friction losses go, I doubt there would be anything major. But I will let you know by the time I finish building my bike. I still need to get accessories which will arrive on Thursday.
And wear to me doesnt bother me because buying an entire heavy duty performace clutch with brown friction pads cost about $5 from China.
My goal isnt to got 50 mph consistently lol, but to get a very smooth and quiet ride at 30 mph at about half throttle. Plus that will help the engine last long when only going half throttle.
I will try to get a used bike, not sure what kind exactly but probably a Diamond Back.
And wear to me doesnt bother me because buying an entire heavy duty performace clutch with brown friction pads cost about $5 from China.
My goal isnt to got 50 mph consistently lol, but to get a very smooth and quiet ride at 30 mph at about half throttle. Plus that will help the engine last long when only going half throttle.
I will try to get a used bike, not sure what kind exactly but probably a Diamond Back.
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I took apart the green bike today & removed the blown pocketbike engine off the front & removed the front rack. I am going to either mount the pocketbike engine on the back or the new Tanaka 33c engine on the back using a similar v-belt drive but with a 700c wheel that I've already mounted a rim-to-rim drive pulley. Today I drilled (4) 1/8" holes thru the rims & pop riveted those 4 locations for added security. The rims are already glued together.
-Lowracer-
-Lowracer-
Yeah, 50mph isn't fast on a bicycle....until you hit the brakes, or get a shimmy. Good idea using the heavy duty DH frame. A lot of DH riders hit 40-60mph frequently in offroad conditions.
Happycheapskate,
Motorizing a DH MTB was the best thing I ever did by accident. Now, I'm thinking how to capitalize on that idea & make lightweight, efficient, powerful, strong motorbikes for all to buy...lol
Nah...just dreaming...
-Lowracer-
Motorizing a DH MTB was the best thing I ever did by accident. Now, I'm thinking how to capitalize on that idea & make lightweight, efficient, powerful, strong motorbikes for all to buy...lol
Nah...just dreaming...
-Lowracer-
A small difference might make it or break it ! (18hp v twin Briggs on "bicycle" home made straight guage frame) 1915 Cyclone Board Track Racer replica - YouTube
