Topic: What a chain guard is for PART TWO (HELEK SH'TAYIM)

[medic09]

I always thought the chain guard was just to prevent oil and stuff from getting thrown up at the rider.  Today my bike shed it's chain at about 90 mph (outrunning a tailgater and trying to get to the right hand lane).  The chain guard is absolutely mangled.  Makes me realize what that could have done to me.  The sprocket cover has a crack, but nothing broken as far as I can tell.

Now, since I have no chain breaker or grinder, how do I remove links to shorten my new chain to 88 and get my bike on the road for tomorrow's commute?  I can then go to the salvage place in the afternoon to get a chain guard (if he has one).

Lesson learned:  check chain tension every 600 miles like the owner's manual says.  I ride that much in a week, and haven't checked the chain since shortly after getting it installed last fall.   

[mlinder]

I'm glad to hear you are ok. A broken chain at 90 mph can have disastrous results.
Dunno how you can shorten your chain, sorry.

[Patrick]

If you have a rotary tool, grind or cut the heads off the link pins from the last link you want to remove. Tap the link pins free with a punch. Move your master link. That's the way a guy at the cycle shop told me a few years back and I've done it that way several times since.

Patrick

[TwoTired]

You broke a 630 chain? 

Did you shoot it a few times with a 9mm first to get it to break?

On a standard chain you can dremel off the peened ends of the pivot pins, and then drive them out through the other side.  I'm not sure if the same technique applies to oring chains.

Cheers,

[Patrick]

I've also done it with o-ring 530 chains.

Patrick

[Green550F]

I had a chain go on my dad's suzuki 185!
I was doing 60 with the wife on the back at the time.
The chain wrapped around by the hub, but luckily didn't lock up the wheel.
The worst part was the long walk home, listening to the wife as I pushed the bike five miles!

[medic09]

You broke a 630 chain? 

Did you shoot it a few times with a 9mm first to get it to break?

On a standard chain you can dremel off the peened ends of the pivot pins, and then drive them out through the other side.  I'm not sure if the same technique applies to oring chains.

Cheers,

The working theory is that since I hadn't kept the chain adjusted/tensioned, it was loose and accelerating at highway speed is what facilitated it slipping and breaking.  I'm glad it didn't end up in a windshield behind me.  Come to think of it, I don't know where it did end up...  My chain guard is sure mangled.

I haven't got a rotary tool, but I saw the PO of my Triumph (retired engineer) tonight.  He suggested just filing a bit on the peened ends, then putting a similar sized punch to  the pin and hammer it out.  Says that's what he often did over the years.

[old750]

It might be hardened to the point where it will ruin your file.

[medic09]

It might be hardened to the point where it will ruin your file.

So what's the suggestion?

[bryanj]

Bite the bullet and buy a chain breaker tool or a dremel. Only other option is try asking nicely/grovelling at a cycle or possibly garden machinery type shop

[ken736cc]

Check your engine cases directly foward of the countershaft sprocket. When these chains go, they sometimes take the engine cases with them. (personal experience) The damage is usually hidden under the accumulated chain lube and goo. I hope you got lucky.

[billstron]

I love the look of our bikes without a chain guard, but your story has convinced me not to take it off.  I often ride with my wife, and I couldn't bear amputating her leg with a broken chain.  I would never hear the end of it  

I'm glad you're ok. 

[BobbyR]

Just chuck a cheapl grinding stone into an electric drill and grind down the pin and then punch it out. Should cost uou $5.00

[BobbyR]

Just chuck a cheapl grinding stone into an electric drill and grind down the pin and then punch it out. Should cost uou $5.00

[Tvag]

Damn that sucks! Glad your ok.

[Lumbee]

...no 4.5" grinder in your tool collection?  If not, every 750 owner needs one with a grinding wheel and a knotted wire wheel, million uses and counting.  Use the grinding wheel to smooth the pins to break the chain.

[puppytrax]

$16.95 at DennisKirk...



It will last you a lifetime...I still have & use the Renold chainbreaker I bought in 1968...along with a half-link and a spare master link, I carry it with me when I ride... 

[gregimotis]

Check your engine cases directly forward of the countershaft sprocket. When these chains go, they sometimes take the engine cases with them. (personal experience) The damage is usually hidden under the accumulated chain lube and goo. I hope you got lucky.

Second that - I punched a half-dollar sized hole in my case that way.

[medic09]

Okay, so SMR (the local shop) cut the chain to 88 links for me.

I got the covers off, it doesn't look like an damage to the case other than a cracked but not broken sprocket cover.

I threaded the chain around, master link in place.  How do you get that front plate to go all the way onto the master link?  Just pressing with pliers isn't doing it.

[Lumbee]

...keep trying, you need to press both sides evenly...

[Patrick]

I use a C clamp.

[medic09]

You guys must have pretty powerful hands with the pliers.  I'm still not succeeding even with the C-clamp.

[Mountainman]

GRRRRR!!! I HATE threads like this! I've been riding for years and years with out a chain guard with not a single bad thought. Never thought about the chain snapping and causing chaos. I guess I'll be putting one on soon. Damn ignorance was bliss. 

[KB02]

Check your engine cases directly foward of the countershaft sprocket. When these chains go, they sometimes take the engine cases with them. (personal experience) The damage is usually hidden under the accumulated chain lube and goo. I hope you got lucky.

That's what I found on my bike when I had the engine apart. There was SOOOOOOOO much gunk in that area that it wasn't until I had it apart that I could see the damage. I'm not sure if the PO did it, or it was the previous PO and my PO didn't even know.

Glad you're okay, though. A Wild chain can cause an awful lot of damage to the human form.

[Drewery]

My chain broke once at about mph and then cramed itself up around the front sproket. It was unbelievable how it got most of itself in there - took me about three hours with a coat hanger fish it out, as the cover would not budge. All it did was damage the light steel guard inside the cover. I only had to bent it back into shape (more or less) and buy a new chain. It is good to have a chain gaurd - now I get nervous looking at my exposed bicycle chain.