Newbie Looking for Advice on a 4-Stroke Kit

GoldenMotor.com

jimijuma

New Member
May 19, 2012
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0
0
Lexington, Kentucky
Hey guys,

I have spend the past couple hours reading various threads on this forum and there is a wealth of info. I wish I would have discovered it sooner.

Anyways, a little about me. I am a dental student and am looking to build an alternate means of transportation as well as a source of fun entertainment. Being a dental student, my time and funds are pretty limited, but getting a reliable motorized bike up and running would have quite a few benefits.

So after reading a ton on this website my initial thinking is to go with a 4-stroke kit mainly due to the reliability, although I am open to advice from the experts. It just seems that the 2-strokes are hit and miss and require more repairs and do not last as long. That would be a major hangup for me as my time is very very limited these days. I want this thing to be very reliable.

So I have been perusing the web for 4-Stoke kits and there are so many. The price seems to range from $190 to $599. I would like some advice on what kit would be a great value. I am sure there are many riders on here that have had several. What 4-stroke kit would you recommend and why?

As far as the bike goes, I will be getting an old steel frame mountain bike on CL. There are plenty and it won't be hard finding one. The question is, should I get the kit first and then get a bike that I am sure will be able to accommodate a 4-strone engine?

Basically, any advice for setting up a 4-stroke motorized bike would be greatly appreciated. Thanks guys.
 

Sidewinder Jerry

Well-Known Member
Dec 19, 2011
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Rockwood, TN
Here are important questions to consider when building or buying for yourself or others:

1) What is the predominant riding terrain?
(Level ground, hills, asphalt or dirt etc...)

2) What type of physique does the primary rider have?
(Large, small, short, tall or health issues etc...)

3) What will the rider's local laws allow and require them to have?
(Lookup and personally read these laws.)

4) What kind of bike is being motorized?
(Mountain, road, whizzer or recumbent etc...)

5) What is the bike to be used for?
(Shows, long trips, around town, off road or racing etc...)

6) How much of a budget is to be used for the build or buy?
(All at the start or as you can afford projects etc...)

Seek the answers to these questions in order to get the most out of the bike you're building or buying. We're here to help with any questions you may have. The purpose of the "Questions to Consider" is not to overwhelm or confuse you. Rather help you focus in on what will work best for you and help you develop a building and/or buying philosophy. This site has lots of people who can help you but the only way they can is by asking questions. Any one of the questions to consider somebody here can help you with.

A fool never learns from their mistakes.

A smart person learns from their mistakes.

A wise person learns from the mistakes of others.

Good luck with your build or buy.

"I became rich by hiring people smarter than me". Andrew Carnegie
 

Sidewinder Jerry

Well-Known Member
Dec 19, 2011
1,996
928
113
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Rockwood, TN
I personally used Staton Inc. But there's several good dealers out there. I recommend getting answers to Questions to Consider before buying anything. It seems you already have some of them answered. Different setups work better depending on what you want. Good luck.
 

jimijuma

New Member
May 19, 2012
3
0
0
Lexington, Kentucky
Here are important questions to consider when building or buying for yourself or others:

1) What is the predominant riding terrain?
(Level ground, hills, asphalt or dirt etc...)

2) What type of physique does the primary rider have?
(Large, small, short, tall or health issues etc...)

3) What will the rider's local laws allow and require them to have?
(Lookup and personally read these laws.)

4) What kind of bike is being motorized?
(Mountain, road, whizzer or recumbent etc...)

5) What is the bike to be used for?
(Shows, long trips, around town, off road or racing etc...)

6) How much of a budget is to be used for the build or buy?
(All at the start or as you can afford projects etc...)
Yep, I read through those questions in older threads. This helped me lean in the 4-stroke direction. Here are my answers:

1 - All the above

2 - No health issues. 5' 11", 170 lbs

3- Under 50cc

4- Steel Frame Mountain Bike

5- Around Town, Minimal off-road, camping (mild dirt and gravel roads)

6- $300 - $400 range, not including the bike.

I just need some advice on what 4-stroke kit to buy. There are several out there and the price range is fairly wide. I am sure others on here have some experience with some of the kits out there.
 
Last edited:

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
Here are important questions to consider when building or buying for yourself or others:
(etc)
Good advice and step one.
What fits your needs now, and how skilled a mechanic you are (including having the tools).

2-strokes are pretty easy and quick to build if you get some help with the rear wheel sprocket, and they will usually hold up a few hundred miles.
And for ~$250 disposable.

If you have the budget, time, talent and tools then by all means go higher end.

My last personal ride (Bad Mojo) re-sold for $1,195, more than I had into it after a year of riding.
I loved the feel of the bike but got tired of 2-stroke and having to pedal to start it even though it was a 1-pedal quick fire 3-speed.

You ask about 4-strokes and that is why I stopped in, I am building one right now, Big Red, a 49cc pull start cent clutch 4-stroke 3-speed shifter om a candy apple red Macargi frame with some attachment changes like seat and handlebars so far for my next new personal ride.

Though I wouldn't recommend a 2-stroke shifter build for a rookie, this 4-stroke shift kit build has actually been really flexible, especially once I actually went and looked at instructions after just assuming it went together the same way the 2-stroke shift kits do.

This just happens to be an opportune time to show you the bottom side of a 49cc 4S on a SickBikes Jackshaft shifter motor mount base and the bottom bracket replacement parts in for the freewheel sprocket.



Yes, it is complex but I do love how adaptable that SBP motor platform is, not to mention how strong their 3-point mounts are.

I don't have the actual jackshaft installed on it yet, I just finished up the bicycle drive part this morning trying to decide on which chain guard to use.

My point in regards to your asking about 4-strokes I am going that way, I've built a couple and a direct drive isn't that hard with a little help and ingenuity depending on the bike and mount kit.

Now let me ask you a question.
Black or Red chain guard on Big Red?





Note that they are identical chain guards and the kit has a plastic ring I painted red, due to the motor mount and distance between the crank arm and sprockets I get a stock guard on but just torn between colors and would just as soon get it right before I flip it over and not so easy.
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
KCvale: The Red chain guard....no question.

So where did you get that 4-stroke kit, how much was it, how was the installation?
My wife agrees, the red chain guard it is ;-}

I would normally go with the $360 http://gasbike.net 4-stroke belt drive kit, but they were out so I bought just the motor and transfer case from bicycle-engines.com for $340 and the http://sickbikeparts.com $200 4-stroke shift kit which provides all the mounting and bottom bracket stuff I wouldn't use from a whole 4-stroke kit anyway, and then used a throttle and gas tank I had in stock.

A regular direct drive 4-stroke kit like this gasbike kit build was a bit tricky in this little Macargi Touch bike...



The Skyhawk motor mount platform didn't want to fit that small frame so I had to do some grinding/drilling work to get the platform mounted but after that it was easy.
On a larger frame the job would be easier.

Looking back on that build I am bit disappointed in myself for not painting that chain tensioner gray.
In consolation it barley needs one anyway and it is in the perfect place, if it should happen to come loose and travel in it will hit the rim and not go into the spokes.

I dumped the swept back handlebars on the touch so it wasn't so cramped and once you wound her up she'd really cruise but I am going for a close as to no pedaling as I can get a 4-stroke direct drive isn't that, it's the 'old Pinto' analogy for me.

If you don't mind pedaling to get going from a dead stop and you want reliability then go 4-stroke, that motor should outlast the bike twice over if you change oil regularly.