Here are the part numbers. You need the R(ight) side dropout to add a derailleur. I found mine several years ago on ebay Australia. Good luck.

Dropout kit: Specialized part numbers: L: 9898-4240/R: 9898-4245

Tyre sizes
 

Hi everyone, I have had my centrum sport for a few years and just love it. Reading this thread, I didnt realise 29 rims would fit. I would prefer to leave the rims as the originals but would like a bit more tyre. Can I go from the 26x1.50 to maybe a 26x1.75 or a 26x1.9 as long as the tyre pattern is not that aggressive or can I only go to 29x1.5. Thanks for any help anyone can give me.

I have a 29x2.0 Schwalbe Furious Fred in the front. In the back there is less space. 29x1.35 Schwalbe Racing Ralph.

Updates to my Centrum - Internal Dropper post routing!
 

Here's mine with lots of changes from spec:

• Shimano MT35 650b wheelset with centerlock hubs, Deore 160mm centerlock rotors
• Panaracer Parimoto 650b x 42c tires w/ Gravel King casing (made in Japan!)
• Origin8 B-Wing Pro bars
• Spurcycle bell
• Internally-routed SDG Tellis 150mm dropper post (great for putting your feet flat on the ground when stopped)
• Shimano BR-M446 hydraulic disc brakeset
• Syntace F109 60mm stem

Unfortunately I can't post pics/links until I hit 10 posts first, which is really dumb! So if you wanna see it, google the keywords 'bryanus.com globe centrum'. My blog post has detailed changes to my bike over the years as well as more info on the internal routing.

https://www.bryanus.com/2008-special...m-singlespeed/

Nice bike! I like the handlebar!

Yeah it's funky, but looks cool and is very comfy! And Thank You for posting my link! slowly getting to 10 posts.... ;-)

Dude I need this part pls!
 

“Update: I managed to find the part on eBay through a seller in Australia.”

can you help me get the hanger for the Ryan side I wish to also put the radio on the rear for my 10-year-old centrum sport
Thanks, Geoff

You'll have to try your luck searching online or through a helpful specialized dealer. The same dropout was also used in some Rockhoppers. The part number is 9898-4245. Good luck!

Installation guide for Centrum/Rcckhopper dropouts
 

Wondering what is the hanger number again?.Is it R: 9898-4245 and where did you order it..Im from Canada.

That's the correct part number. You can't order it from anywhere anymore. It's no longer being manufactured. Might find one on eBay or a shop if you are lucky.

Thanks...Ebay is too expensive almost $80cdn shipped..wonder if there is a alternative ?..Anyways your bike looks great.Unique.

wow that seller is gouging! His first sales started at $18 AU! But amazing that he's sold 24 of 30...who is buying these I wonder? Centrum or Rockhopper owners?

wow that seller is gouging! His first sales started at $18 AU! But amazing that he's sold 24 of 30...who is buying these I wonder? Centrum or Rockhopper owners?

https://www.ebay.com/itm/26259517793...item3d23e46dd2