CrossRider SBP shiftkit 8speed hub gears

[Jonda500]

CrossRider with sturmey archer hubs
After road testing the hub gears I moved the twist grip gear shifter to the left handlebar to make way for the throttle

It has 8 speeds, drum brakes and a dynamo front hub

I laced the CMC rims onto the hubs using new spokes in a 4 cross pattern

I moved the original friction shifter to the left handle bar and hooked it up to the clutch
I don't know wich picture I am writing under!
CrossRider bicycles were made in Australia in the 80's by the Graecross Cycle company.

2.7/2.6 inch tyres

straight forks, the steep steering angle makes it a very quick steering bike!

 

[Jonda500]

21 tooth left side cog, 9 tooth right side turning a 36 tooth chainwheel

brand new nos rubber pedals made in japan!

good for putting along pedal assisting or burning along ghost pedalling : )

hooked the hub up to some old dynamo lights

love the crossrider badge

still no idea which pic I am captioning!

 

[Jonda500]

I had to pull the front wheel slightly down in the fork slots for room for the fat tyre

the rear wheel kept pulling crooked and throwing the chain so I fitted an old bmx chain adjuster

the bmx chain adjuster kept bending out with accompanying loud cracking noises until I bolted it to the rear of the dropout

the rear wheel sprocket and final drive chain wheel are 25 and 24 teeth

when in first gear the hub gives a gear ratio of one to one the gears get taller from there

The chains are showing signs of rubbing despite having clearance?! but the transmision of power and the gear shifting is smoother than my other 4 builds. When slowing down to stop, I pull the gear lever operated clutch first and then use both brakes with both hands, -changing back to first to take off is simple with hub gears! : )

 

[Jonda500]

So now that I've solved the problem with the axle pulling forward, the feckin hub keeps twisting around no matter how tight I do up the wheel nuts! (Only the axle and hub gear cable entry rotate, the brake side can't rotate as it has a brake torque arm holding it) This is going to be more challenging to fix. I'm really not sure what to do! -at least the gears don't go out of adjustment when it happens coz luckily it pushes the gear cable rather than pulling on it.
Does any one know if you can get sturmey archer specific chain adjusters with slots instead of round holes? (the axle is round but with the top and bottom flattened, the wheel nut washers slot onto the axle and have little tangs that slot into the dropouts to prevent the axle turning. Coz of my backwards derailliuer dropouts I have to have the tangs in front of rather than behind the axle and they seem to be gradually bending the lower part of the dropouts down!)

 

[wheelbender6]

Beyond cool. Love the Sturmey hubs. A longer fork would slow the steering a bit if it is too twitchy for you. My mountain bike steered too quick for me (at cruising speed) and I moved the kit to a cruiser bicycle.

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[Jonda500]

Update- I stuck in a teeny little shim (between the bottom of the axle washer tang and the top of the lower drop out and chain adjuster slot) and took it for a spin expecting this to make no difference at all, but, when I got back the axle (and gear cable) hadn't twisted around any where near as far so I left it where it was and slightly adjusted the gear cable route to suit the new exit angle. Problem solved!
Then today I changed the driven (inner) chainwheel from 36T to 30T raising the gear ratio in 1st from 8.75 to 7.3 to 1. Still a plenty low enough 1st gear to take off up hill and a higher top speed down hill(I have no speedo on this bike but I think around 70km/h). Easier to start now- I only weigh 65kg and now my full weight on the pedal will get it turning without having to bounce on the pedal whilst yanking up on the bars! -however it's not suited to pedal assisting any more Some how one tooth of my 24T outer drive chainwheel got bent over!?! - I straightened it without it breaking off (phew!) and it seems fine now, but...
The higher speed seems to have killed the dynamo- I'll have to do some more checking to be sure but the bulbs are ok and the wiring looks ok so it's not looking good!

 

[KCvale]

Nice job Jonda.

The chains are showing signs of rubbing despite having clearance?!

You have both your sprockets on the same side of the freewheel, you can get a little more chain clearance by putting the outside sprocket on the outside of the freewheel.

That of course is going to be much harder to do now that the pedal has been thoroughly torqued into the freewheel however, we generally have to put the whole thing in a jig to keep the freewheel removal tool in place and put a cheater bar on the socket wrench to break it free.

I am curious as to why you put the sprockets on backwards, was the back tire to fat?

 

[Jonda500]

I solved the chain rubbing dilema -this is a little embarrassing- the jackshaft to chainwheel chain is the one that was previously on my mongoose which is where it got its evidence of rubbing- I hadn't noticed that it was slowly cutting into the frame after I'd tightened the cranks several times (I've banged the damaged area in out of harms way now and braized over it to restore strength).

Once I had the idea, I simply had to try reversing the chains to see if it was possible and assess if I thought it was a better set up. It was tricky on the mongoose getting enough room for 7 speed derailliuer gears whilst maintaining chain clearance. The crossrider was much easier coz of its hub gears and because it has much more room between the frame & chainwheel.

I like the result -the jackshaft chain is tucked in right in out of the way of my leg/jeans, the 9T gear is reversed so the teeth wont be sawing into my leg if the bike ever ends up on top of me, the overall width of the bike is noticably narrower, the final drive chain is easier to put back on if it comes off(the mongoose chain has come off twice, the second time I put it back on the chainwheel with my foot without stopping!), when the chain comes off it doesn't break anything as it comes off the outside and is left hanging around the pedal crank(it can't fall between the chainwheels because the rotating jackshaft chain throws it out!) and I think the appearance is much neater.

In both cases to to get the final drive chain to sit far enough inwards for perfect alignment with the rear wheel sprocket, I had to mount the outer chainwheel on the inside of the freewheel and also had to use the original narrower pedal crankshaft in both cases(for the 7 speed I aligned the chainwheel with the 4th gear sprocket).

With some chainwheels the one on the outside of the freewheel wont come off without unscrewing the freewheel but the SBP chainwheels can be changed without removing the freewheel from the crank.

I agree that the freewheel is a challenge to remove! I bolt the tool to the crank so the dogteeth can't come out of the slots, then clamp it tightly in the vice and with the pedal removed use a long pipe slid on to the crank to undo it, gradually loosening the bolt as it undoes.

 

[Patchy]

Good build man! Also, have you thought of getting the secondary coil for your lights? Dynamos aren't worth it in my opinion.

http://www.ebay.com/itm/12-VOLTS-MI...ng-/400108733087?rd=1&ssPageName=STRK:MESE:IT


There is also a 6volt version.

 

[Jonda500]

I've changed the Mongoose outer chainwheel from 36T to 30T as the gearing was too tall as it is above. First(34T) and sixth(15T) gears are now 6.35 and 2.8 to one. (Previously they were 5.3 and 2.4 to one)

Even with a sprung seat it is wise to lift your weight off the saddle for large bumps!

 

[Jonda500]

Good build man! Also, have you thought of getting the secondary coil for your lights? Dynamos aren't worth it in my opinion.

http://www.ebay.com/itm/12-VOLTS-MI...ng-/400108733087?rd=1&ssPageName=STRK:MESE:IT


There is also a 6volt version.

I have the 6 volt one with led light & switch on another of my bikes - it sapps the power a bit so I have to raise the idle speed when the light's switched on, but it has been reliable, though I do wish I had bought that 12 volt one (cheaper!) and used one of the lights I already had!

 

[KCvale]

Don't ya love internal shifting hubs?
No 7-speed dinky chain, just solid single speed chain with all sprockets aligned.
Again nice build ;-}

 

[Jonda500]

thanks! I absolutely love internal planetary gear hubs - an amazing, complex engineering feat that I don't dare try and explore inside, where as to purposely derail a chain seems haphazard and crude at best! (and I'm getting sick of my derailliuer chains coming off!)
When I first purchased the hubs I was hopeing to be able to run without a rear wheel freewheel, but I didn't realise the planetary transmission gears only work in one direction- when wheeling the bike backwards the cranks rotate with the wheel like it's in first gear no matter what gear you put it in!

I chose the 8 speed for the wider range between first and top gear despite thinking it might be tedious having so many gears, but although from second through seventh the ratios are indeed very close I still more often than not use all the gears.
If I double click and only use every second gear it does ride nicely as a five speed too however.

 

[KCvale]

thanks!
I chose the 8 speed for the wider range between first and top gear despite thinking it might be tedious having so many gears, but although from second through seventh the ratios are indeed very close I still more often than not use all the gears.
If I double click and only use every second gear it does ride nicely as a five speed too however.

I find a simple 3-speed internal to be ideal for a motorized bike unless you have a lot of hills and then a 5-speed to give you that in-between gear between 1st and 2nd.

Like your 8-speed internal I 'double click' gear ranges on derailleurs too, usually just the even number gears as an engine has way more torque than your legs ;-}