Motorized Bicycle Engine Kit Forum  
Register FAQ Members List Calendar Mark Forums Read




Sponsors
To be a sponsor Contact Us
Donations accepted!
Our Forums


Go Back   Motorized Bicycle Engine Kit Forum > Bicycle Motor > 4 Stroke Bicycle Engines & Kits

4 Stroke Bicycle Engines & Kits 4 stroke motorized bicycle engine kits are great if you want reliability or do not want to mix your oil and gas. Learn from each other how to get the most out of your 4 stroke bicycle engine

SBP 4 Stoke Prototype


Discussion at Motorized Bicycle Engine Kit Forum in the 4 Stroke Bicycle Engines & Kits forum. Originally Posted by glacknoid Houghmade: Where exactly did you drill a hole, at the end of the pipe on the ...
Reply
 
LinkBack (4) Thread Tools Display Modes
  #21 (permalink)  
Old 04-01-2009, 09:33 AM
HoughMade's Avatar
Motorized Bicycle Elite Member
 
Join Date: Apr 2008
Location: Valparaiso, IN
Posts: 626
Default Re: SBP 4 Stoke Prototype

Quote:
Originally Posted by glacknoid View Post
Houghmade: Where exactly did you drill a hole, at the end of the pipe on the bottom of the fat part? And does it help.

Yes- right in the center...and- other than being a bit louder, don't know if it did anything. I was making a lot of changes when I did that and I cannot tell if that change did anything. All I can say is that it runs fine, a bit louder than stock, bit that's fine with me.
__________________
29/10ths cubic inches of raw power.
HoughMade at WIRED.com: http://www.wired.com/cars/coolwheels...memade_bicycle
Reply With Quote
  #22 (permalink)  
Old 04-01-2009, 11:04 AM
Quenton Guenther's Avatar
Dealer
 
Join Date: Feb 2008
Location: Outer Banks of North Carolina
Posts: 193
Default Re: SBP 4 Stoke Prototype

Hi Easy Rider,

Do you mean like this?

Have fun,
Quenton
Get YOUR EZmotorbike TODAY!
Attached Thumbnails
SBP 4 Stoke Prototype-mvc-136f.jpg  
Reply With Quote
  #23 (permalink)  
Old 04-02-2009, 09:38 AM
Ghost0's Avatar
Motorized Bicycle Elite Member
 
Join Date: Mar 2008
Location: Bellingham, WA
Posts: 638
Default Re: SBP 4 Stoke Prototype

Well I finally got to take her for a spin and I must say it is pretty fun. Completely different experience from the 2 stroke, of course it is on a Cruiser as apposed to a MTB. The torque is pretty awesome but it doesn't seem to pull top end like the 2 stroke but then again that is the difference between a 2 stroke and 4 stroke. So I am in the process of double checking all the hardware and adding lights and speedo, etc and the weather is supposed become decent again by this weekend so I should be able to get some performance figures.
__________________
Design is easy, execution the hard part.
www.sickbikeparts.com
Reply With Quote
  #24 (permalink)  
Old 04-02-2009, 11:19 AM
Quenton Guenther's Avatar
Dealer
 
Join Date: Feb 2008
Location: Outer Banks of North Carolina
Posts: 193
Default Re: SBP 4 Stoke Prototype

Hi Ghosto,
My 4 stroke pulls very hard on the top end, and easily out paces a 138 CC Whizzer up to 37 MPH [top speed with current ratios]. When cruising at 20 MPH and grabbing a "handfull" of throttle it will lurch forward with serious gusto.
After testing it against the "Hoot" & "Grubee" gearboxes it soon becomes clear that the EZM drive system doesn't eat up most of the power in the gearbox [the EZM doesn't use gears or grease], and the loud "singing" noise is gone.
Of course the EZM flex exhaust system sure doesn't hurt the power any, and appears to allow the motor to vent the the spent gases more freely.
The most common asked question is "I know you are well known for pulling power from a motor, so what have you done to the EZM?" Other than changing the exhaust sytem the motor is 100% stock, and I only changed the exhaust for cosmetic reasons.
I am going to run the STOCK 49 CC 4 stroke on the "Roller Road" in Dawson Springs, KY next month, and I will share the results on this site.

Have fun,
Quenton
Get YOUR EZmotorbike TODAY!
Reply With Quote
  #25 (permalink)  
Old 04-02-2009, 11:30 AM
Pablo's Avatar
Master Bike Builder & Forum Sponsor
 
Join Date: Dec 2007
Location: Duvall, WA PNW
Posts: 2,848
Default Re: SBP 4 Stoke Prototype

My 67 cc modded China motor with SBP shifter kit easily pulls away from Whizzers, so that's not a huge thing IMHO.

We'll need to see your gearbox to see if we can adapt it to our jackshaft. The goal is to get away from the "bolt on spoke bender" and use the bike's gears.
Reply With Quote
  #26 (permalink)  
Old 04-02-2009, 12:23 PM
Motorized Bicycle Newbie
 
Join Date: Mar 2009
Location: texas
Posts: 1
Default Re: SBP 4 Stoke Prototype

how do u get the crank from turning on it wile the engines runing
Reply With Quote
  #27 (permalink)  
Old 04-02-2009, 12:31 PM
Ghost0's Avatar
Motorized Bicycle Elite Member
 
Join Date: Mar 2008
Location: Bellingham, WA
Posts: 638
Default Re: SBP 4 Stoke Prototype

muder 15
There is a freewheel in the chainring assembly allowing you to pedal the bike but once the engine speed becomes faster than your pedal speed the pedals can remain stationary.
__________________
Design is easy, execution the hard part.
www.sickbikeparts.com
Reply With Quote
  #28 (permalink)  
Old 04-02-2009, 01:14 PM
Quenton Guenther's Avatar
Dealer
 
Join Date: Feb 2008
Location: Outer Banks of North Carolina
Posts: 193
Default Re: SBP 4 Stoke Prototype

Hi Pablo,

Consider the following........
When compairing a single speed 4 stroke EZM [49 CC]against a single speed 4 stroke Whizzer [138 CC], the larger displacement Whizzer has a hard time keeping up. If the Whizzer or the EZM were able to use your shifter system it would be an advantage over the single speed. For example if the Whizzer could change ratios it would most likely out run the EZM, or if the EZM were to use your shifter kit it would only increase the amount the EZM would be out front.
It is also important to relay a few more interesting facts, we started with ratios of 22 X 1 and soon found the motor maxing out the RPMs. We continued to change the ratios to cause the motor to "hit the wall", and because of the desire to cruise within the 4 stroke's torque curve we ended up with a production ratio of 16.3 X 1. Our kit will easily exceed the current top end speed by changing the ratios. When I displayed the proto-type at Lewes, DE last year it was geared at 17.56 X 1 and went faster, both in take off and top speed. Both the Honda & HS 49 CC 4 stroke motors will reach into the higher RPM levels when the "drag" is reduced, and both motors find RPMs above 8000.

With our current ratios the motor is only turning 6350 RPMs at 30 MPH [38 @ 8000 RPM].

Your shifter kit would most likely increase the top end of our motor above 45 MPH, and also take off faster. The ability to "shift" would be an advantage in hilly terrain, and an advantage with heavier riders.

Have fun,
Quenton
Get YOUR EZmotorbike TODAY!

Last edited by Quenton Guenther : 04-02-2009 at 03:11 PM.
Reply With Quote
  #29 (permalink)  
Old 04-02-2009, 06:35 PM
glacknoid's Avatar
Motorized Bicycle Elite Member
 
Join Date: Oct 2008
Location: robbinsdale MN
Posts: 150
Default Re: SBP 4 Stoke Prototype

GHOST: Does it seem like it doesn't pull the same top end because the gearbox does'nt produce the same rpm's at the output or because it doesnt' have the torque it takes at high rpm to push the bike? Would a step up or down with the final sprocket on the jackshaft make for better top end?

Last edited by glacknoid : 04-02-2009 at 06:42 PM.
Reply With Quote
  #30 (permalink)  
Old 04-02-2009, 07:21 PM
Ghost0's Avatar
Motorized Bicycle Elite Member
 
Join Date: Mar 2008
Location: Bellingham, WA
Posts: 638
Default Re: SBP 4 Stoke Prototype

All good questions which I don't have an answer to yet. I haven't put a speedo on it yet so it is really hard to judge speed. It may be singing right along but I just don't know it. My initial feeling is that it is geared a bit tall and I may go down to a 9 tooth on the jackshaft but is still starts from a stop without assist very easily so only more testing will tell.
__________________
Design is easy, execution the hard part.
www.sickbikeparts.com
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

LinkBacks (?)
LinkBack to this Thread: http://motorbicycling.com/f37/sbp-4-stoke-prototype-7047.html
Posted By For Type Date
One very cool video - Bob Is The Oil Guy This thread Refback 03-31-2009 03:54 PM
One very cool video - Bob Is The Oil Guy This thread Refback 03-31-2009 08:35 AM
One very cool video - Bob Is The Oil Guy This thread Refback 03-30-2009 02:02 PM
One very cool video - Bob Is The Oil Guy This thread Refback 03-30-2009 01:56 PM


All times are GMT -5. The time now is 09:00 AM.


Sponsors
To be a sponsor Contact Us


Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2010, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.3.2
Motorized Bicycle Engine Kit Forum


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71