How do you identify wbx pulleys for timing?

Big lumps of metals and spanners.

Moderators: User administrators, Moderators

Locked
silverbullet
Trader
Posts: 16346
Joined: 08 Jun 2009, 09:51
80-90 Mem No: 6908
Location: Surrey Syncronaut #156
Contact:

How do you identify wbx pulleys for timing?

Post by silverbullet »

More specifically, what does a 10 degree BTDC notch look like compared to a 5 degree one?

My maths says that on a 166mm dia (triple pulley) 1 degree = 1.45mm at circumference, so 10 degrees measures about 14 or 15 degrees from TDC.

Sounds like a silly question but it's not in the wiki :wink:

User avatar
itchyfeet
Registered user
Posts: 12427
Joined: 23 Jul 2007, 17:24
80-90 Mem No: 12733
Location: South Hampshire

Re: How do you identify wbx pulleys for timing?

Post by itchyfeet »

The circumferance can be calculated from the 170mm diameter x 3.14 , it means 5 degrees is about 7.5mm around the circumferance on a standard pulley so 10 degrees is 15mm
easier imo than trying to measure angle in degrees
u shape is tdc v shape timing mark, engine rotates clockwise so timing mark is to the rhs (clockwise) of tdc for btdc timing as dg dj, other way round for atdc timing as on df
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

silverbullet
Trader
Posts: 16346
Joined: 08 Jun 2009, 09:51
80-90 Mem No: 6908
Location: Surrey Syncronaut #156
Contact:

Re: How do you identify wbx pulleys for timing?

Post by silverbullet »

I said it was a silly question! Must be the heat....although all the pulleys I have are 10 degree ones.

User avatar
itchyfeet
Registered user
Posts: 12427
Joined: 23 Jul 2007, 17:24
80-90 Mem No: 12733
Location: South Hampshire

Re: How do you identify wbx pulleys for timing?

Post by itchyfeet »

Reading your post again you had it right, you just wrote 15 degrees rather than 15mm and i thought you were trying to measure degrees :lol:
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

Locked