[If You Build It]

I ride a 2005 Specialized P.2 which has the old ISCG hole spacing. The stock chainguide broke and I wanted to get an E-Thirteen guide. They offer both a chainguide with the old ISCG hole spacing as well as the now-standard ISCG-05 spacing. The dilemma is that I will likely buy a new frame in the medium-term future which will undoubtedly use the ISCG-05 standard. The ISCG-05 chainguide comes with an adapter that you mount under the BB cup, but the adapter will not fit unless I grind away the ISCG-old tabs on the frame.

Should I:

1) Buy the guide with the new spacing, grind away the old tabs, and use the BB adapter. I will then be able to move this chainguide to my hypothetical future bike.

or

2) Buy the chainguide with the old spacing because [insert reason using the BB adapter is a bad idea] and [insert a way that I can make a guide with ISCG-old spacing work on my hypothetical future frame]

PS: Does anyone have any helpful tips for using the BB mounting scheme or special considerations for grinding aluminum?

 

[jackiecovert]

Hi there mate,

I think you should go with the first option and Buy the guide with the new spacing, grind away the old tabs, and use the BB adapter. I will then be able to move this chainguide to my hypothetical future bike.

 

[jonKranked]

only real downside i would consider is if you're planning on selling your p frame when you get a new one, grinding off the tabs might hurt the resale value.

also, generally i'd recommend not using the BB mount adapter plate. i've had so so luck with them; on harder impacts there's a good chance they'll shift from the impact.

why not pick up a used chainguide that's iscg old for the p.2? then sell it with the frame and get an iscg 05 when you get the new frame?

 

[If You Build It]

I have solved the problem with what I think is hands-down the best solution. In researching, I found out about Specialized's completely awesome lifetime frame warranty policy. If the frame ever breaks (which was always the plan anyway, ride it till it breaks), Specialized will send you out the most similar new frame for the cost of shipping. There are tales on the internet of people buying a Specialized and then getting 4 free frames over the years as each replacement frame snapped in some way.

I'm the original owner, and grinding off my tabs would most likely void this warranty, so instead I found a way to grind the chain guide adapter, which is the little aluminum bracket that sandwiches between the BB cup and the frame. I didn't have to grind off very much of it, and if I did weaken it to the point that it breaks in a crash, it's only a $12 part. Admittedly, it's a bit of a janky way of mounting a chain guide, but:

Successful mount - check
Frame warranty intact - check
Able to transfer chainguide to future bike - check
Got to grind metal (always fun) - check

Now I just have to wait for something to eventually snap on that frame. But considering that the aluminum P bikes of that era are built like tanks, that may be a while. I have a feeling that my bike will be old enough to drive before something on it breaks.

 

[jonKranked]

yea spesh is def good on their warranties - but are pretty strict on the whole original owner aspect (best if you have the receipt).

when i turned wrenches we had a dude come in with a 14 year old rock hopper frame that cracked, they sent him a new one no questions asked.

 

[WestCoastHucker]

i guess i'm confused as to why you wouldn't just buy the correct guide now, then just get a new backplate when you get a new frame?