Cannondale BB30 24mm adaptor - can I fit a chainguide?

hoodlum-z

Can I fit a BB chainguide (roller) to a Cannondale RZ140 Carbon frame, as it doesn't have ISCG tabs? The plastic adaptor sticks out of the BB30 shell about 10 or 12mm on the drive side and I am running a Shimano SLX crank and bottom bracket.

With a normal BB shell it is a standard procedure, but it is the plastic 24mm insert that I am concerned about. Does it make any difference to instalation?

I intend to fit a Black Spire Stinger and Chain God C4 bash ring, simply because they are cheap and look to do the same job as the likes of Gamut and e-thirteen.

Any advice would be helpful.

Thanks.

nicklouse

ok shimano do not make a BB30 crankset. so what have you got fitted?

is it BB30 or is it one of the shimano press fit ones. BB90/BB86/BB92?

hoodlum-z

I have a 2010 Shimano SLX bottom bracket and chainset with 24mm spindle. The BB is of the outboard bearing variety. The cups screw into the frame, or into the adaptor in my case.

With a normal English BB shell, like on an old steel frame for instance, the chain guide would sit between the frame and the drive-side BB cup.

What I'm concerned about is the fact that if I install the chain guide in the same way it will be sitting between the BB cup and a plastic sleeve. Would this be strong enough?

Ideally I need to know if someone else has overcome the same problem.

nicklouse

so what adapter are you using to fit the BB30 BB? a reducer in the bearing or a pressed in sleeve and external cups?

pics.

hoodlum-z

http://cdn.cannondale.com/Manuals/2010_ ... oms_en.pdf

Nick,

Think you can follow the link, if not if you go to the Cannondale support section on their website, there is a supplement for RZ120 and RZ140 and if you scroll down the PDF document there is a clear diagram of the plastic insert.

After studying this diagram I think I will be okay to install the chain guide; essentially it is converting my BB30 shell into an English shell.

As long as I only run a roller and not a tacco bash plate then it should be strong enough. Obviously a tacco sends shock forces through the plate and into the BB shell, whereas a roller is only being held in place and isn't stressing the BB in any way. My bash ring is simply replacing the big chain ring.

Cheers, mate.

nicklouse

I Always thought they were Aluminum. is the frame ally? if yes dont worry too much as it can always be re done. and if Carbon it is a bit more permanent.

so treat the BB as a standard 68mm one and lose one spacer for the guide.

hoodlum-z

Mine is a carbon frame, but only the front section - top tube, head tube, down tube. The 3-D forged backbone, seat tube, is aluminium on all the RZ frames.

Yes, mate, like you say I'll remove one spacer and hopefully everything should be fine.
Even though the insert is plastic, it should be pretty solid.

Thanks.

idenry

Just wondering how you got on with this?
Hoping to do the same job on my Rush with BB30.

hoodlum-z

Dude,

I opted for the heim3, which they don't seem to be making anymore, though they are still doing the heim2, which has a totally different design. Get one while you can from Chain Reaction.

All I did was remove the nearest washer/ring to the frame (my BB had two spacer rings on the drive side) and it went straight on, dead easy to fit.

You can still go to 2 chain rings and replace your big ring with a bash if you want, so I thought the heim3 was more versatile than the heim2 if I decide to change in the future. I don't really ride over many logs or big rocks so I might as well keep my big ring instead of a bash. Even if you only use it rarely - it's still nice to have.

By the way, the roller makes a slight noise, but this is far outweighed by the reduced chain slap. Overall I'd say it is a much quieter system and I haven't dropped a chain since it has been on.

I honestly don't know why the heim3 device isn't more popular. It is the only 3-ring security device on the market. Perhaps though that once people ride their trail bike so hard they keep dropping chains, they've already moved onto a 2-ring setup and roller.

If there is anything else you want to know, just ask.

Cheers