How to figure what motor suits the rider?

GoldenMotor.com

KINGLOOIE

New Member
Jan 13, 2012
15
0
0
MONTANA
.xx.I am kinda on the fence to a 66cc or a 4 stroke. I am a big fella 6'2" and 275 lbs. I know its going to take some snort to get this mass moving. Any thought from the peanut gallery? Besides a diet!!

Thanks for your time
Kinglooie
 

andrewflores17

New Member
Jul 12, 2010
479
2
0
colorado springs, CO
you could go with a low gear to get you moveing a little easier id vote for the 4 stroke with the ezm kit . a 2 stroke would work two i just favor the thumpers
whats your local terain lotsa hills or flat
gear head experince how well can you turn a wrench

with this we can help you narrow it down a little better
 

happyvalley

New Member
Jul 24, 2008
784
1
0
upper Pioneer Valley
By definition, some pedaling will be inherent with all motor assisted bicycles, being single speeds, at starts, out of corners, on acceleration etc. In a sense, gearing matters more than engine choice and it depends if you want low end torque to easily get up to a modest cruising speed or pedal more at the start to attain a higher top speed. More than that and a scooter or motorcycle starts to make more sense.
 

Nashville Kat

Well-Known Member
Apr 20, 2009
1,501
55
48
Jacksonville, Florida
I weigh as much as you- I'm all the way down to a 34 alloy sprocket in back- and still have to do almost no pedal assist- if I wanted- that's with a 66 two stroke with a short billet intake and 66 speed carb- I have plenty of power on flats here and cruise 25-30 on the speedo with the throttle about 1/2 to 2/3 open- which really gives a quiet and smooth cruise-

http://www.ebay.com/itm/34-T-Sprocket-Bicycle-Engine-Kit-Motorized-Bike-/110803639691

I also have a 50 build- 39 alloy sprock-not so fast- but REALLY lightweight cruiser and rides very much like a roadbike with 700c tires.


I'm from a road racing background so I like the bike to be as peddable as possible- The 66 is a cruiser with 27 inch alloy wheels- and I'm always shutting off and coasting or else just peddling in parking lots or near the retail places that are my usual destinations. Its' like having a regular bike with afterburners- I eliminate the motor tensioner with a derailleur and use a very lightweight great rolling 415 trike chain- so whatever a kit weighs by itself- I've taken POUNDS off with alloy sprocket, light chain and not using the tensioner. And I always use alloy bars and 3 piece alloy cranks and pedals.

I find the two cycle convenient and easy to use- I used to be a bike mechanic- so that's another factor- a four cycle is a bit more mechanical challenge and you usually need wide cranks-

on the other hand if you don't want to pedal much at all, , the 4 stroke may be better for you. And a bit more quiet I think.
 
Last edited:

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
By definition, some pedaling will be inherent with all motor assisted bicycles, being single speeds, at starts, out of corners, on acceleration etc. In a sense, gearing matters more than engine choice and it depends if you want low end torque to easily get up to a modest cruising speed or pedal more at the start to attain a higher top speed. More than that and a scooter or motorcycle starts to make more sense.
To clarify: your definition may be true with motor assisted bicycles, which is one reason why we prefer differentiating between the terms "motor assisted bicycle" (usually reserved for under 1hp or less and/or pedalic only systems) and "motorized bicycle" (general term for a bicycle with any type/size of motor). Deciding that a scooter or motorcycle makes more sense than anything other than a limited "assist" system is a matter of personal preference and not specific definition in this instance.

In actuality this isn't relevant to the question at hand as in the OP's home state of Montana there appears* to be no such "assist" restriction, gears are allowed so long as it's an automatic & it seems in Montana, a moped falls under the definition of a bicycle - pedals are only required to be exempt from registration if you would so choose.

Which means should the OP wish - he could build a multi-speed 50cc/2hp motorized bicycle with an automatic or variator-style transmission and would be completely within the law & has been proven by any number of mopeds, pedaling would be at the operator's discretion, if at all.



*please confirm your local area's laws for yourself, I could be mistaken ;)
 
Last edited:

Budz

New Member
Jan 16, 2012
11
0
0
Atlanta
.xx.I am kinda on the fence to a 66cc or a 4 stroke. I am a big fella 6'2" and 275 lbs. I know its going to take some snort to get this mass moving. Any thought from the peanut gallery? Besides a diet!!

Thanks for your time
Kinglooie
I would go for a lower gear. I,am running a 41 tooth. You may want to try a 39 tooth, this will get the bike going quicker at lower speeds.

Budz
 

KINGLOOIE

New Member
Jan 13, 2012
15
0
0
MONTANA
I love a good forum...They seem to help weed the mistakes down to a minimum....NOTE I said a minimun ....hehehhe Any and all input is usefull.brnot
 

KINGLOOIE

New Member
Jan 13, 2012
15
0
0
MONTANA
After some research I am sorta leaning toward a gt5-sr a super rat? with a internal cdi. They seem to have more top end power, maybe with some gearing and clutch work it would be the ticket to my tubby butt? hehehe

On another note my son pulled his scooter motor, a 49cc yhc(robin?) off his scooter and it has a transmission on it. Would need to change the carb and get the nessary other parts but it should be a descent motoer for a magari falcon gt w/26" wheels....think this is a good start for him??
 

happyvalley

New Member
Jul 24, 2008
784
1
0
upper Pioneer Valley
By definition, some pedaling will be inherent with all motor assisted bicycles, being single speeds, at starts, out of corners, on acceleration etc. In a sense, gearing matters more than engine choice and it depends if you want low end torque to easily get up to a modest cruising speed or pedal more at the start to attain a higher top speed. More than that and a scooter or motorcycle starts to make more sense.
To clarify: your definition may be true with motor assisted bicycles, which is one reason why we prefer differentiating between the terms "motor assisted bicycle" (usually reserved for under 1hp or less and/or pedalic only systems) and "motorized bicycle" (general term for a bicycle with any type/size of motor). Deciding that a scooter or motorcycle makes more sense than anything other than a limited "assist" system is a matter of personal preference and not specific definition in this instance.
In actuality this isn't relevant to the question at hand

Who is the "we" dictating preference? I must have missed that as well as the notice that there is a final arbiter on what is relevant with such exactitude that any further comment or opinion beyond would fall outside the strict precision of general discussion on a wrench turners message forum. Now aware, I'm sure I'll notice equal and precise regimentation exercised on a cross section of threads, lol.
 
Last edited:

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
No one but yourself can dictate your personal preferences happy, I was simply trying to clarify that while your description for "motor assisted" was correct, in the OP's home state of Montana they're not subject to the limitations described by such. That it's to abide by or recommend those limitations when local law allows more - your statement "More than that and a scooter or motorcycle starts to make more sense." that is what would be a personal preference - what makes sense to the rider is up to the rider ;)
 

happyvalley

New Member
Jul 24, 2008
784
1
0
upper Pioneer Valley
Yes, I do sense some confusion, but then I guess that's why the perceived need to clarify is often quite subjective.

Nothing was implied about the laws of MT nor any legal definitions, rather about the physics of what the OP asked. Following the logic of a thread titled How to figure what motor suits the rider, the OP initially stated "I know its going to take some snort to get this mass moving". The meaning of my comment was simply stating all bicycles have pedals by definition and IMO that to expect more from a bicycle with a motor, whether we call it a motor assist or motored lol, that at some point if that isn't sufficient from a practical viewpoint a scooter or motorcycle might make more sense. Rather simple really, certainly not a solution looking for a problem.

By definition, some pedaling will be inherent with all motor assisted bicycles, being single speeds, at starts, out of corners, on acceleration etc. In a sense, gearing matters more than engine choice and it depends if you want low end torque to easily get up to a modest cruising speed or pedal more at the start to attain a higher top speed. More than that and a scooter or motorcycle starts to make more sense.
 
Last edited:

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
...excepting ofc it isn't inherent with a motorized bicycle that it must be a "single speed" in which case a 2hp motor with with an automatic or variator-style transmission would indeed have both "snort to get this mass moving" as well as "a higher top speed" - thus "to expect more from a bicycle with a motor" than simply an "assist" is both practicable & reasonable, without resorting to purchasing a scooter or motorcycle, which I would think if the OP were interested in such - they wouldn't be here.

Minor points to be sure, but there are some inherently critical differences between the rudimentary single speed motor assist that you described "by definition" and the potential that exists within the general classification of motorized bicycle & in fact given the interest stated, including the title and the physics involved - I thought it prudent to mention that indeed more can be expected as well as achieved, thus the second half of my post.
 

SlowBalt

Member
Mar 8, 2010
759
6
16
Rhode Island
Hear is my 2 cents on engine choices. I have built 8 2 stroke bikes so far.
And i can tell you all the engines look almost identical ,but the internals are all different. so far the best most dependable and powerfull out of the box have ben the X-80 from Lucky Early Bird on eBay And the z-80 from Boy go fast. they both are available with standard frame front casting and wide frame style front casting so no adapters are needed. x-80s z-80s small front mount. z-80 x-80 large mount. currently on the 2 bikes I ride my x-80 has 3000mi 36 tooth rear on it, and my z-80 is on my race bike with just over 500 mi on her 30 tooth. With a 44 tooth and these engines you will be able to cruse around 35 mph and climb most hills with ought touching the pedals.
On a sidenote to handle the extra waight I would get hub clamp style sprocket adapter from one of the site venders ,rather than letting tiny spokes bear the brunt .
 
Last edited:

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
After some research I am sorta leaning toward a gt5-sr a super rat? with a internal cdi. They seem to have more top end power, maybe with some gearing and clutch work it would be the ticket to my tubby butt? hehehe

On another note my son pulled his scooter motor, a 49cc yhc(robin?) off his scooter and it has a transmission on it. Would need to change the carb and get the nessary other parts but it should be a descent motoer for a magari falcon gt w/26" wheels....think this is a good start for him??
Yes & I think so lol - as I was attempting to state previously both those engines are quite sufficient, tho given the weight stated I would recommend some manner of gearing to provide both a satisfactory take off as well as a comfortable cruising speed ;)

In regards to your son's scooter motor, a "49cc yhc(robin?)" which provided it's in good condition most likely has more power than the GT5 as it's likely a far higher quality engine - the "I think so" is simply due to the fact I'm unfamiliar with the physical dimensions of that engine & transmission combo, so I'm not sure what would be involved with trying to fit it to a magari falcon...

Tho I will say given the potential quality of that engine as well as the fact it has a transmission, it's definitely worth pursuing - dependent only on how much modification & fabrication you're willing to do :D
 

happyvalley

New Member
Jul 24, 2008
784
1
0
upper Pioneer Valley
By definition, some pedaling will be inherent with all motor assisted bicycles, being single speeds, at starts, out of corners, on acceleration etc. In a sense, gearing matters more than engine choice and it depends if you want low end torque to easily get up to a modest cruising speed or pedal more at the start to attain a higher top speed. More than that and a scooter or motorcycle starts to make more sense.
...excepting ofc it isn't inherent with a motorized bicycle that it must be a "single speed" in which case a 2hp motor with with an automatic or variator-style transmission would indeed have both "snort to get this mass moving" as well as "a higher top speed" - thus "to expect more from a bicycle with a motor" than simply an "assist" is both practicable & reasonable, without resorting to purchasing a scooter or motorcycle, which I would think if the OP were interested in such - they wouldn't be here.

Minor points to be sure, but there are some inherently critical differences between the rudimentary single speed motor assist that you described "by definition" and the potential that exists within the general classification of motorized bicycle & in fact given the interest stated, including the title and the physics involved - I thought it prudent to mention that indeed more can be expected as well as achieved, thus the second half of my post.
I see the confusion persists. Either that or a pattern of harassment is beginning to take shape here. Read my post which I have already included several times in subsequent replies. You might notice the words definition and bicycles are both in italics used to imply a connection. You might also see that the comment 'being single speeds' is one in a list of several physical obstacles that one encounters overcoming inertia. I further address that by then talking about gearing, etc. to attain what one is looking for in performance. Why the continued insistence on parsing my comments with a fine tooth comb to suggest they mean something other than they do I am at a loss for.
 

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
I'm simply attempting to expand on and add clarity in what was offered as a "definition" as it seemed to infer less that what is not only possible, but recommended in this case.

As an example - in your own home state of Massachusetts* a "motorized bicycle" is defined as a pedal bicycle which has a helper motor, or a non-pedal bicycle which has a motor and a displacement of 50cc or less with an automatic transmission, which runs contrary to what you had stated as "inherent". Such would be the importance of inclusive details within proposed definitions.

I'm sorry you feel that it's either confusing or harassment, but a forum is for the discussion of topics in this fashion - up to and including expounding on points made by others as well as the exchange of dissenting opinions *shrug*


*http://www.mass.gov/rmv/forms/20017.pdf
 

happyvalley

New Member
Jul 24, 2008
784
1
0
upper Pioneer Valley
I'm simply attempting to expand on and add clarity in what was offered as a "definition" as it seemed to infer less that what is not only possible, but recommended in this case.

As an example - in your own home state of Massachusetts* a "motorized bicycle" is defined as a pedal bicycle which has a helper motor, or a non-pedal bicycle which has a motor and a displacement of 50cc or less with an automatic transmission, which runs contrary to what you had stated as "inherent". Such would be the importance of inclusive details within proposed definitions.

I'm sorry you feel that it's either confusing or harassment, but a forum is for the discussion of topics in this fashion - up to and including expounding on points made by others as well as the exchange of dissenting opinions *shrug*

*http://www.mass.gov/rmv/forms/20017.pdf
First off, the linked pdf is out of date by a decade. The MA laws were updated in July 2009 with a third class of two wheeled vehicles added where there had been two.

Massachusetts RMV - Moped Definition and Requirements

This is the 4th post directed at my one initial comment, 4 out of 17 before the last. I have the sense that near 25% of the posting in the entire thread, contributing little to the OP's original comment but rather skewed to "correct" mine, is suspect. I am not the one confused but I do suspect this is harassment.
 

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
Then you should take that up with Mass RMV as it's what they still provide regarding motorized bicycles - but even within the link you've provided no mention is made of pedals, the specifics remain the same.

I do believe the number of replies made is proportional to the number of statements made & I think such constitutes a discussion, "harassment" usually infers hostility, an overt attack of some sort - which I assure you I did not intend nor I believe is evident, the intent being again - clarification. If you don't wish to continue a discussion - don't.