Cranks and Chainrings

[kenloen]

tell me, does any chainring fit any crank? I have a Profile Racing 3 piece crank but no chain ring. I like the Tuf neck chainrings but am unsure it they fit (the ones without the spider). Also, how many teeth is good - there are loads avaiable 42,43 44 teeth?? being fitted to a 86 PK Ripper..

cheers Jason.

[MartyC]

Yep, any one piece chainring will fit any one piece or cor-moly 3 piece (Redline/Profile/Terrycable, etc) crank however you may need to get a Top-Hat washer to make them fit a 19mm axle, the size of the washer will depend on the chainring as they can vary a little.

http://www.alansbmx.com/product_info.php?cPath=32_34&products_id=2343&osCsid=c189a54cbf1b797680c45c1d7f663a14

Marty 

[brettypeeps]

Chainrings come in various sizes and most people prefer 44t

Spiders and complete chainrings can come with a 19-23.8mm hole in the centre. Most but not all Redline 3 piece cranks are 19mm but some are 20mm and a standard 1piece crank is 23.8mm. There are adapters to convert a 23.8mm chainwheel to 20mm or 19mm and these are the top hat washer

As for fitting chainrings to spiders they either have a 110mm or 130mm offset so choose the chainwheel to match your spider
Or choose the same make to be sure. 

[kenloen]

Ah, I know my crank axle is 19mm because I was advised on what BB to buy recently. So if I buy a 1 piece 4 bar chainring I will also need a 22-19mm tophat.. got it.. many thanks..

will hopefully have pics up soon..

[john4130]

it wont be a 22-19 tophat  you'll need it'll most likely be a 15/16"-19mm. opc are 15/16" and most old chainrings came in this size to fit them. it wont be hard to find a tophat washer in this size tho.

[HEYWOOD BMX]

  Most oldschool spiders/chainrings have a 23.8mm centrehole-to fit a Tufneck onto Profiles you`ll prob need this size down to 19mm tophat washer:)

[The VW Doc]

Sorry to hi-jack a little, bit I am looking for a spec for the nuts & bolts to hold the chainring to the spider (as I am wanting to replace them with stainless steel ones) and not having any to go on is making it a little difficult

Can anyone assist please?

[MartyC]

Sorry to hi-jack a little, bit I am looking for a spec for the nuts & bolts to hold the chainring to the spider (as I am wanting to replace them with stainless steel ones) and not having any to go on is making it a little difficult

Can anyone assist please?

You need single chainring or outer chainring bolts like these:



Usually 6mm thread depth 

[The VW Doc]

Cheers Marty - Why are they externally threaded but still hollow? Weight ,or does soemthing screw into them?

I haven't got the spider yet, so I am waiting to see how that fits, but the chainring is not threaded

(Sorry for the Newbie questions)

[MartyC]

Cheers Marty - Why are they externally threaded but still hollow? Weight ,or does soemthing screw into them?

I haven't got the spider yet, so I am waiting to see how that fits, but the chainring is not threaded

(Sorry for the Newbie questions)

No worries, they will have another section to screw into like these ones...



They are generally hollow to save weight 

[The VW Doc]

Ah ha! makes sense! Thanks mate