# Bashguard for 20" Hotrock



## Fletch F. Fletch (Feb 15, 2005)

Help! My son has broken the flimsy stock chainguard/bashguard on his 20" Hotrock. Now the chain falls off all the time (despite having cool little chain pulleys by the chainring). I suspect the chainguard played a role in the chain retention system. Can I order an aftermarket bashguard that fits? I looked and the bolt circle for the OEM chainguard is a 5 hole pattern and everything I've found (so far) is the standard 4 hole pattern... Thanks!


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## IAmHolland (Jul 8, 2010)

i can check as i have a hotrock 20. you'll probably want to measure it to see if it's the 110 BCD, which is 5 hole. if i'm not mistaken, it's also riveted and would require modifications as it's a one piece crank.

that said you shouldn't be dropping your chain even without it. it sounds like something got misaligned. take a closer look at it. you can also adjust the double rollers, they are not pulleys as they have no spring tension by themselves. they are held on by the bottom bracket and 4 socket headless screws.


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## Fletch F. Fletch (Feb 15, 2005)

I've got the rollers super close to the chainring but my kid keeps dumping the chain. Granted, he drops it when he is going off jumps... You don't want the rollers actually making contact w/ the chainring do you? I've got 'em about as close as you can get. 

If I were to find a guard w/ the same bolt circle diameter and timing, could I just use chainring bolts to attach?


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## IAmHolland (Jul 8, 2010)

it's rivited, you'd need to drill. do measure to make sure it is a 110bcd. you'd need spacers as well. the crank is really 1 piece.

i'm not entirely sure it'll fit, but have power tools, will do.

check out the bbg bash guards.

The chain guard should touch, yes. It should take up the slack in the chain.

http://www.specialized.com/us/en/bc/SBCBkModel.jsp?spid=47708&eid=4360&menuItemId=9270










notice how it is pushing up on the chain from the bottom. The top part is more or less straight up. The looseness is probably why your chain is dropping. When you tension the chain, shift to the large cog to make sure you can still reach it.


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## moto367 (Nov 20, 2006)

Have you checked the derailleur hanger? They are really flimsy. My son was all the time bending his until I finally put a different one on and that helped a lot. You stated that you have the rollers close to the chainring...make sure they're in line as well.


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## Fletch F. Fletch (Feb 15, 2005)

I replaced the deraileur hanger recently (you're right, the stock hanger is super weak...but props to specialized for spec'ing the same hanger that goes on the big bikes so you can find them in shops). And the rollers appear to be aligned as well. I think it's an issue of the chainguard/bashguard missing since the rollers aligned right and the deraileur hanger is straight/true. Thanks everyone for your help!


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## dieseldork (Oct 20, 2011)

Awesome information. I am in the process or rebuilding a 20" hotrock for my son. This thread has some great info.


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## indianadave (Apr 27, 2010)

My daughter doesn't jump hers. She doesn't have the rollers, or chain gaurd on it. I did take some links out, and re-aligned the rear derailer hanger. I also have a Sinz crankset and front 32T chainring.She's taken some single track downhills pretty hard, and bounced over some rocks and roots, and has never dropped a chain.
I think you need to check all your teeth on the gears. Maybe they're really worn?


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