SBP shift kit for cantilever Schwinn?

[silverbear]

I'd appreciate some advice on the suitability of an SBP shift kit for the bike pictured below. I found this bike at the dump last summer and haven't done anything with it yet. Even though it was in very good shape and was ridable as it was I kind of looked down on it since it was made after Schwinn was no longer American made. But I did notice that the bike seemed to have really nice components and everything was in very good condition... no rust on the wheels, etc. and the spokes were pretty thick and solid... wheels still true after all these years. I'm guessing this bike was made not too long after the company was sold.

In my ongoing quest for a bike capable of these mountains in Maryland while pulling the dog trailer, I've been thinking about this cantilever Schwinn and warming to the idea of giving it an SBP shift kit. I would of course give it a new paint job, probably black, a seat and chainguard from the fifties and a front springer fork from a 51 Schwinn with a V brake I rigged up for it. I would use the wheels which are pictured with new tires. The engine is a PK-80 from Pirate Cycles with a killer SBP expansion chamber exhaust. In frame gas tank made by Tinsmith.

My questions have to do with whether or not this frame presents any problems for the kit. It looks to me like there should be enough room behind the seat post, but you guys who have experience know better than I do. The bike is in Minnesota so I can't look at it other than in the pictures below until I get home again in a month, but it looks like five gear sprockets to me. That should be about right, yes?

I notice that the bottom bracket uses a one piece crank and in looking over the kit hardware it looks to be made for a three piece BB. Is this going to be a problem? Can I adapt it? There must be a way since Barelyawake used such a kit on his old Rollfast, right?

The information at SBP suggests that the standard kit is for a low compression engine and I'm guessing that the slant head PK-80 has high enough compression that I would need the heavy duty version.

Would I need to change the axle on this rear wheel? The site says that regular steel axles will bend under the torque from this setup. How can I know what axle this has and how big a deal is it to change it over? Could I just slip one in from a newer mountain bike?

One last question: the engine I have has a pull start I installed on it. Will there be clearance issues with the pedal crank which comes with the kit?

This is new territory for me and I appreciate your thoughts on this. I've come to like the cantilever Schwinns and now have a few gas tanks for them. Assuming the opening is close to the same as the ones from the fifties, I should have a copper tank already to mount once the frame has been painted. I know this can be a good looking build, but if the frame is not suitable then I'm fighting things. The engine I know will plug right in for a nice fit in the Schwinn frame. This would be a summer build, some ways off yet, but I like to plan things out and be ready when the time comes. If this is a poor candidate for the shift kit I'd like to know now rather than later. Many thanks,
SB

 

[skjjoe]

Silverbear.. I am sure some one else will chime in but I think the shift kit will work fine on that bike. It looks allot like my jag frame. You will have to convert the B.B. but I think I got the kit for that from SBP. Just remember there is a right and left side to the bearing cups. As far as the pull start goes i cant tell you. I dont have one. But it looks real close to me that's why I haven't got one yet. Oh and go with the heavy duty kit its got a much better freewheel. I would not worry about the rear wheel for now I didn't change mine and have no problems........yet. Good luck. Post pics
Scott

 

[timboellner]

I think your frame looks like there is plenty of room for the jackshaft.

You only need 1 1/2" from the back of the seat tube to the tire for clearance.
You will need to get the bottom bracket adapter so you can convert to a 3 piece BB set-up. It's an easy install. Sick Bikes has them .

Sick Bike Parts

The kit comes with the sealed bearing bottom bracket cartridge.

The pedal cranks come with the kit already. You will have to supply your own pedals. I believe they are the larger of the 2 pedal size threads. 9/16ths?

I recommend changing the rear axle to a chrommoly one. I wouldn't use a quick release axle set up either, even though they are chrome moly.
I bent 2 regular steel axles. I've also snapped a QR axle and slightly bent a chrommoly one. Careless shifting, or a mis -adjusted derailer can bang the shift hard enough to do damage to the axle. I'm rough on stuff.
The problem lies in the fact that a freewheel hub
has a lot of unsupported axle hanging out between the wheel bearing on the freewheel side and the frame drop outs. The narrower width of a 5 speed freewheel may have a slight advantage over a comparitively wider 7 speed hub.

Amazon.com: Wheel Master Cro-Mo MTB solid axle

Chrome moly axles are a black color and standard axles are shiny bright metal.
They are not hard to swap out either. Remove the jam nut and cone on the non-freewheel side and slide the axle right out of the hub from the opposite side. Watch out if they are the loose ball bearing type wheels cause they'll fall out and make you say bad words. Clean and repack, install the cones and jam nut on the freewheel side of the new axle, slide it in and do the non-freewheel side last and you're done.

I don't know how wide the pull starter width compares to the standard magneto cover but I measure 1" pedal clearance to the standard mag. cover.
if it's less than that it will clear.

I don't know about the cheaper freewheel, but I'm sure the HD freewheel
is the way to go from a longevity and reliability standpoint. I know they are pricy but are extremely well made.

I hope any of this is a help to you.
Once you shift gears you will wonder how you went all this time without that ability, especially if your pulling a heavy load like a trailer.
TiM

 

[The_Aleman]

Yup, more than enough room on that frame. Heck, you could 4-stroke and SBP that frame with no problem, long as you stuck with the 5/8" shaft equipment.

 

[silverbear]

Thanks for the excellent input, you guys. It looks like a go to me and I'm getting enthused about it. Sounds like lining up a chrome moly axle would be a good idea at the very least to have on hand if and when the stock one dies of stress. The plan for now is to prepare the frame for paint when I get to Minnesota, change over the front fork to a 51 Schwinn springer with a V brake setup using the stock front wheel. Once the bike is painted and back together I'll mount the in frame gas tank, the copper one I think, give it new tires, lights, fenders, a refurbished vintage seat and use the bike as a rider for awhile to be sure all is as it should be regarding the brakes and gears. I'd like for it to look like a 50's Schwinn with the exception of the multi speed aspect. Turning the bike into a motorbike will wait until I have the shift kit, probably toward the end of summer. Then I can fit up the PK-80 and run the expansion exhaust, hopefully down low and under the BB. If there's exhaust interference with the center kickstand then I'll need to make up a rear drop stand for it. Come fall I'll bring the bike with me to Maryland and there I'll be asking Timboellner for some advice once I have the kit installed. There's nothing like the practiced eye of experience to look things over, making sure I have done things right. Then I think I'll be ready for the challenging inclines of the Catoktin Mountains where there are so many great places to ride on back roads through beautiful forest. I'll start a thread on this build once I'm back home and ready to begin. I'll post photos as I go. This bike will be in the background somewhat since Fasteddy will be coming from B.C. so that we can get to work on our Indian tri-car builds (his a tribute 1904 and mine a tribute 1909) and another canoe sidecar. What a summer of riding and building to look forward to... woohoo! May this childhood never end. Thanks again you guys...
SB

 

[The_Aleman]

Mounting fenders should also be no problem, I know you rock fenders proudly on your classy builds

Look forward to seeing more.

 

[silverbear]

Mounting fenders should also be no problem, I know you rock fenders proudly on your classy builds

Look forward to seeing more.

I like the looks of a bike, both ways, with and without fenders. Without gives more of a "hotrod" look and says "I'm fast". But I find that in actual riding I don't like road junk getting kicked up on me and I do like a more classy look. I ride in all weather I can get away with including slush, so fenders make good sense for me.
On a slightly different subject, have you had any issues with your shift kit? What kind of bike are you running and with internal or external gears?
This is not to be an ultimate, no expense too great, build for me as I'm on a budget as always. The external gears are there on this bike and the reason a shift kit came to mind in the first place. I'm guessing the conversion will come to around $250.00 for the HD version with shipping and BB adapter. Add another $50.00 for new tires and I have a bike worth having. If I were starting from scratch I might not do this, but the bike appears to me to be a good one, I have an engine and killer exhaust for it, already have the in frame gas tank and the other stuff from donors. Should turn out to be a great bike.
SB

 

[The_Aleman]

Yeah, I loved how my bike looked without fenders or front bag and those 2.2 red-lined slicks, just had that "hotrod" look like you said. Even here in Cali when the sun shines in December and it's 70F or so, all it takes is a minor puddle to throw up brown spots all over your clothes. So fenders it is, especially since like you I also ride rain or shine. Been in my share of slush in other states, too. I'm experimenting with Planet Bike polycarbonate quick-release fenders right now, so far so good. Traditional Walds don't look right on my bike lol

As for my shift kit, sure I've had issues with it, but I was expecting them since I was one of the first along with ocscully to put a Honda-style 4G on the SBP 4-stroke mount last year. I went with the same hub as BarelyAwake's, a Sturmey X-RD3 3-speed with drum. The hard-working guys at SBP hadn't even tried a 4G on their mount at the time, and I was told I was going to have to notch the engine mounting holes and prolly bend crank arms even with widest crank they give you with the SBP 4s kit. I had issues as soon as I bolted up the mount without engine, a shoddy bolt failure at a key mounting point. I had issues as soon as I hit the throttle in 1st gear after about 300 miles of break-in - the whole mount twisting because of the tremendous torque a 5:1 4G can put out. It's still a little twisted, but it's not moving anymore, even if I pull a wheelie out of first gear (try that with a Q-matic heh). With any build tho, there's going to be a teething period, especially if you're doing something new with a kit, let alone a full-on custom that I had no desire to undertake at the time.

FWIW, I think it's better to have internal gears with a shiftkit just because you won't have to deal with chain alignment as much. Internally shifted hubs can take just about whatever chain you throw on, whether it's Wallyworld Bell BMX, high-grade 41, china 415, or something fancy and idler-friendly like Shadow Conspiracy halflink. Externally-shifted chain for derailleurs is thinner, and it's mandatory if you want to keep your full cog range. It's less forgiving of crank sprocket misposition, which is of course a chain-breaking issue with motorvation lol

I still want to do a 2-stroke on a SBP mount tho. I've lusted after the thought since '06 riding my 7-speed Schwinn Alloy Seven with 34T in the mean Grand Forks, ND headwinds! Look forward to seeing yours.

I like the looks of a bike, both ways, with and without fenders. Without gives more of a "hotrod" look and says "I'm fast". But I find that in actual riding I don't like road junk getting kicked up on me and I do like a more classy look. I ride in all weather I can get away with including slush, so fenders make good sense for me.
On a slightly different subject, have you had any issues with your shift kit? What kind of bike are you running and with internal or external gears?
This is not to be an ultimate, no expense too great, build for me as I'm on a budget as always. The external gears are there on this bike and the reason a shift kit came to mind in the first place. I'm guessing the conversion will come to around $250.00 for the HD version with shipping and BB adapter. Add another $50.00 for new tires and I have a bike worth having. If I were starting from scratch I might not do this, but the bike appears to me to be a good one, I have an engine and killer exhaust for it, already have the in frame gas tank and the other stuff from donors. Should turn out to be a great bike.
SB