Jackshaft Shift Kit from SBP

[TheJimGuy]

Have had my bike running for a year now. Very pleased overall. Have a 26", 7 speed, beach cruiser. I am about to purchase the HD Shift kit from SBP so I can cruise at 28-30 without having the poor motor trying to shake itself apart. It would also be nice to have a bit more acceleration from the get go.
Reason for the post: Any last minute pros/cons/advice prior to me pulling the trigger?

TheJimGuy

 

[Fabian]

Make sure you get the Deluxe option with the heavy duty freewheel, because it also has the necessary and useful tools supplied with the kit.

The SickBikeParts shift kit is a mandatory item and the best thing since sliced bread, and as you've obviously found out, a single speed drive system is a complete waste of time.

You will be most happy with the shift kit and changing gears will put a huge smile on your face !!!

 

[Sidewinder Jerry]

What most people don't get is shift kits are ment to give you versatility more so than speed. It allows you to be in the most efficient gear for the level of terrain you're on. It will also give you better take off response.

I currently have the only bike in the world which shifts 5 gears automatically through a shift kit. I use a custom made 5 speed freewheel I built.

 

[Deleted member 12676]

"a single speed drive system is a complete waste of time"
I totally disagree. My bikes kick ass in every way possible, all with one gear. I was living at an altitude of 8500 ft and the city was hilly. The stock 48cc couldnt handle it. I upgraded to a 55cc, increased compression, redirected the transfers, got a decent carburetor, greatly reduced vibration with a lighter wrist pin and the Jaguar CDI, and resurrected the "outdated" idea of lengthening the intake track for a resonance effect which stuffs more air/fuel mixture in at low rpm. I couldnt be happier. Then I experimented with reed valve and torque pipe and I was literally flying up those hills! People looked on with amazement.
People dont race with a shift kit because it robs 8% of engine power due to the extra sprockets and chain.
Fabian, dont tell me that my ride is ultra-tricked out and beyond the capability of mere mortals. My 55cc (which bolts on without modification) didnt have a reed valve or torque pipe. Any clown can copy what I did and be gut busting happy with it. Only strange thing about the 55cc is the intake bolt spacing is wider at 40mm so when you buy the offset intake (which is spaced at 32mm) you will need to hacksaw where the bolt holes are on the manifold to allow for wider spacing. Then connect the carb to the intake with a 3/4" heater hose (from OReilly) that is 2-3" long. Then you will be like "WTF? Why isnt this kick-ass system promoted by any of the main vendors?" Ha! Because they are promoting more expensive solutions. The extended intake is the poor boys solution.

 

[Sidewinder Jerry]

Here is what inspired me to make the 5 speed autoshift system I use. My state Tennessee has the following legal requirements: 50 cc, automatic transmission, 2 brake horse power limit, level ground speed of 30 mph.

Even though my bike does shift gears its does it totally automatically. The RS 35 engine is 33 cc at 1.6 horse power. In the future I plan to add a 350 watt electric hub to the front wheel. This way I don't exceed the two brake horse power limit. I know a way to activate the regen system on the electric hub so that it will recharge the battery when only using gas.

Because laws vary greatly from location to location it means we have to use many different setups to satisfy local legal requirements.

 

[Fabian]

I totally disagree. My bikes kick ass in every way possible, all with one gear.

I totally disagree with your disagreement. A single speed system cannot have the bike travelling up a 20% gradient, hauling 80 kilos (175 lbs) behind it, yet then travel on flat ground with reasonable road speed, hence the reason why a SickBikeParts shift kit is not just an option but a vital necessity.

greatly reduced vibration with a lighter wrist pin

A single cylinder engine cannot be balanced, with the balance factor only changing the rpm zone where vibration is at it's greatest. Lightening wrist pin and all that jazz will offer some reduction in vibration at high rpm (the 7,500 rpm that you rev your bike to) but will not reduce vibration outside of that zone, and i have discussed this before and supported it with the mathematics of single cylinder engine balancing.

People dont race with a shift kit because it robs 8% of engine power due to the extra sprockets and chain.

A pointless bit of dialogue because the vast majority of people do not race their motorized bicycles, using them only for transport, and also the vast majority of people live in locations where state legislation has either banned their hobby/transport because of people racing motorized bicycles on public streets.

 

[Sidewinder Jerry]

The way the government is we're losing more and more freedoms everyday and they're always looking for reasons to take even more of them away from us. That's way I stress building within you local legal requirements. As well as driving responsibly.

 

[crassius]

Here is what inspired me to make the 5 speed autoshift system I use. My state Tennessee has the following legal requirements: 50 cc, automatic transmission, 2 brake horse power limit, level ground speed of 30 mph.
. . .

Because laws vary greatly from location to location it means we have to use many different setups to satisfy local legal requirements.

I have same kind of laws here, but I purposely avoid automatics or even centrifugal clutch just to be sure my machines are not covered by any law that might require registration or license.

 

[Sidewinder Jerry]

Here in Tennessee if its got any kind of motor on it you must have a valid driver's license. You can voluntarily register and insure a motorized bicycle but aren't legally required to. However if you don't build within the guidelines of Tennessee's definition of a motorized bicycle it can't be driven on the public roadways. Otherwise if the police stop you a ticket will be issued for operating an improper vehicle on the public roadways and the bike impounded.

Therefore if you're going to be using the public roadways comply with your local legal requirements.

 

[crassius]

sounds like freedom is hard to find in Tennessee - you have my sympathies