SBP 4 Stroke Shift Kit Grubee Gearbox

This kit is sweeeeeet! Makes the 4 stroke ride even better...higher speeds with less revs.and fun!Sick Bike Parts are great people to do biz with.You recieve quick answers to any questions you might have during your build.My build was easy and fun using this well thought out kit and mounting system.Take alook for your self

Thanx Motomagz

 

[Ghost0]

The 4G compatible design is in works.

 

[scottyo]

So what are your speeds like on the different inclines/declines/flats?

 

[MotoMagz]

My area is flat ..... have reached 30mph with the engine barley reving and lots of throttle to go.I might put her to the test soon.

MotoMagz

 

[Irish John]

MotoMagz,
Where doesn't one buy a stage II? I've wanted a 4 stroke for so long but everything I read about the 4 stroke gearboxes were that they made a terrible whining noise.

Thanks,
PS Anybody know if Hoot gearbox is good or not? Is Stage II gearbox a replacement for Hoot or vice versa?

Stage 2 is now out of production but Stage 3 is almost identical. They all whine - some not so bad but most are pretty noisy. You get used to it eventually. Putting the SBP kit on a hoot would be a waste of a good jackshaft kit on an inferior Hoot GB. The Hoot GB is the pits.
I reckon you will soon have belt driven GBs available that will make the shifter kit unnecessary but the Grubee G4 will never be any good because it is too wide and wrongly geared (the new amended G4 is still wrongly geared) and the cover falls off because the holding brackets break. Think Grubee Stage 3 with SBP kit or EZM belt drive GB. Unless you rear mount the motor but that is a different scenario completely.

 

[MotoMagz]

I've been playing around with the gear ratios ..swopping out different rear freewheels and and just ordered a 10t sprocket from SBP.I clocked my self on a police portible radar trailer at 39 mph....thats about all I could handle! The kit has been problem free and a blast!


Motomagz

 

[Irish John]

MotoMagz, where did you get that bike with the springer forks that have V-brakes on them and rear V-brakes as well? Great bike for motorising.
Does the derailleur ever throw the chain off when changing up & down the gears and do you wear out the freewhelel cluster on rear wheel?

 

[MotoMagz]

MotoMagz, where did you get that bike with the springer forks that have V-brakes on them and rear V-brakes as well? Great bike for motorising.
Does the derailleur ever throw the chain off when changing up & down the gears and do you wear out the freewhelel cluster on rear wheel?

Irish,The bike is a Schwinn Jaguar and I put an aftermarket springer with V brakes.
As for the derailluer throwing the chain off it has never happend.I did switch my derailuer out for a higher quality so when shifting ..it respones much quicker.The freewheel I just took of looks great with no signs of unusual wear.

Motomagz

 

[Irish John]

Thanks for that info Moto, how good is the aftermarket V-brake on the springer? Does the Jaguar come with a V-brake on a rigid fork and if so is it the tapered steel standard Schwinn fork? If so that is a good twangy fork anyway.
I really like seeing a cruiser without a coaster brake.
Is it steel or alloy frame?

 

[Egor]

Moto I have the same gearbox and it was noisy also, I added hydraulic oil and that helped, I also looked inside and found that the gears were out of alignment also. I changed the shim on the clutch to move it out and meet the other gear better. I noticed you can loosen the back cover and move it around so I moved it closer to the clutch gear, it doesn't have a shoulder to locate on so if you move it closer to the front of the engine you get a better alignment. I also have all the shrouds off the engine and checked with a thermal scanner an found the engine stay cool, under 200 degrease, easy. And I like the look. I am going to cut the fins shorter on the flywheel so I can move the starter in closer. Have fun, Dave

PS: I think your bikes look cool, good job. I like the new one with the Cog belt, it looks cool with the cover off, I love mechanical looks.

 

[Irish John]

I think the Hoot gearboxes all break up inside because the gear wheels aren't properly hardened. The Grubee Stage 2 can be very noisy, just a bit noisy or relatively quiet depending on luck of the draw. Mostly they are noisy if they are more recently made models. The 11T freewheel teeth wear out after about 4000 kms. Getting replacements is difficult now that Grubee have moved on to the 4G gearbox. The Grubee Stage 2 is the best gearbox they have built so far by a country mile because it works well and replacing freewheels, clutch, bell housing and bushing is inexpensive if you can find a Grubee dealer who cares enough about service to stock the parts for their Stage 2 customers. A fixed drive sprocket will wear better than the freewheel because it is harder steel but the fixed sprocket is for a different shaft size and it is 10T which stuffs up the reduction ratio and thus creates a real problem further down the chain.
The 4G is quieter because it is belt driven but the reduction ratio is ridiculously wrong for a 26" wheel and the GB is way too wide and looks pretty ugly.
The Stage 2 is the best of the Grubees in my experience. I'd reckon if Staton make a GB it would be pretty good too but they don't make a frame mounted GB last time looked at their website.