« previous next »
Pages: [1]   Go Down

Author Topic: Timing idler  (Read 827 times)

Offline ShaunMac

  • A's Good Friend
  • ***
  • Join Date: Feb 2013
  • Posts: 128
  • Karma: 1
Timing idler
« on: 12.04. 2014 16:33 »
I know I'm going to look daft posting this but just took the timing cover off due to magneto removal and I've noticed the timing marks don't line up. If I pull the idler gear out just so the teeth disengage and rotate it then they line up.
Am I doing the right thing? *sad2*
Logged
61 Super Rocket swing-arm

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5720
  • Karma: 66
Re: Timing idler
« Reply #1 on: 12.04. 2014 17:29 »
in a word yes, and you will have spotted one set of marks are  dots and the other set  dash's they must match dot to dot dash to dash (sorry if that seems obvious)
The marks only line up once every 80 odd revolutions or 70 can't quite remember, but it matters not, idlers are designed that way so that the same teeth are not meshed every time.
And no questions are deemed daft here (some of my answers maybe) Knowledge is nothing until it's shared
Logged
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline ShaunMac

  • A's Good Friend
  • ***
  • Join Date: Feb 2013
  • Posts: 128
  • Karma: 1
Re: Timing idler
« Reply #2 on: 12.04. 2014 19:10 »
Thanks Bill.
I can strip Diesel engines with my eyes shut but the sentimental value of this engine is making me ask lots of questions. All I can say is this forum is a God send!
Logged
61 Super Rocket swing-arm

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5720
  • Karma: 66
Re: Timing idler
« Reply #3 on: 12.04. 2014 21:17 »
Oh  right - sorry I remember now it's your dads bike, nice project I'll bet
Logged
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline ShaunMac

  • A's Good Friend
  • ***
  • Join Date: Feb 2013
  • Posts: 128
  • Karma: 1
Re: Timing idler
« Reply #4 on: 12.04. 2014 21:31 »
There's two things that have really got to me on this rebuild...the person who originally built this bike for my dad as whoever it was has cut a lot of corners and also my brother who stored it for 10 years and just started it up every now and then for a run down the road and killed the engine.
The connection I have with this bike is more than you can imagine and even though I work everyday with all types of vehicles the reassurance from everyone on here helps me so much.
I know that the day she fires up there'll be a big smile from me and from above.
Logged
61 Super Rocket swing-arm

Online RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 6387
  • Karma: 55
Re: Timing idler
« Reply #5 on: 13.04. 2014 00:35 »
So, Shaun, I take it the bike was not running with the idler marks misaligned? The marks on the idler are really just a convenience to make sure the dot on the crank pinion and the dash on the cam gear simultaneously point at the exact center of the idler spindle/bush. As long as they do, lining up the marks really wouldn't matter. Now, no one here, including myself, would recommend ignoring the marks, but I was just wondering if the previous builder just got lucky with the cam and crank position.

Richard L.
Logged

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4528
  • Karma: 41
Re: Timing idler
« Reply #6 on: 13.04. 2014 05:19 »
 At risk of stating the obvious *conf*, The crank dot and cam marks should be in 'alignment' position every two revolutions, irrespective of where the idler marks are, and said idler should be able to be removed and replaced with all marks in correct alignment....someone tell me if I'm wrong, as this is an easy check/shortcut....???

 anybody have the right change for two bob?
Logged
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline WozzA

  • Wise & Enlightened
  • *
  • Join Date: Nov 2011
  • Posts: 1480
  • Karma: 18
  • Melbourne Australia
Re: Timing idler
« Reply #7 on: 13.04. 2014 08:03 »
dots on crank....   dashes on cam...    *smile*
Logged
'51 Golden Flash Plunger
'57 Golden Flash Swingarm

Melbourne
The biggest lie I tell myself is
"I don't need to write that down, I'll remember it"

Offline ShaunMac

  • A's Good Friend
  • ***
  • Join Date: Feb 2013
  • Posts: 128
  • Karma: 1
Re: Timing idler
« Reply #8 on: 13.04. 2014 09:09 »
The idler was about 6 teeth out. Moved it round and it lines up dot - dot & dash - dash.
Have to say I'm loving working on the bike, just wish I had a bit more knowledge on them.
Every days a school day!
Logged
61 Super Rocket swing-arm

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5720
  • Karma: 66
Re: Timing idler
« Reply #9 on: 13.04. 2014 09:33 »
Quote
and said idler should be able to be removed and replaced with all marks in correct alignment

of course Dutch, however with it off it's so easy to move something and forget - must have been done hundreds of times (even hundreds of times plus one  ;))

and will four tanners do  *smile*
Logged
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline Topdad

  • bob hebdon
  • Wise & Enlightened
  • *
  • Join Date: May 2011
  • Posts: 2596
  • Karma: 36
  • l
Re: Timing idler
« Reply #10 on: 13.04. 2014 10:30 »
Posh Sod Wozza,  showing of your SRM pump, *grins* very clean though ,cheers Bobh
Logged
" rules are made for the guidance of wise men and the blind obediance of fools"
United Kingdom

Offline WozzA

  • Wise & Enlightened
  • *
  • Join Date: Nov 2011
  • Posts: 1480
  • Karma: 18
  • Melbourne Australia
Re: Timing idler
« Reply #11 on: 13.04. 2014 12:39 »
Quote from: Topdad on 13.04. 2014 10:30
Posh Sod Wozza,  showing of your SRM pump, *grins* very clean though ,cheers Bobh

Not Posh Bob....   more like a LUCKY BUGGER...   
Thanks to mark from this site who came to my rescue ...  & sold me it for MUCH less than it cost him. *wink2*
what I like about this site & our members... is their generosity & willingness to help out when they can.   *beer*
Logged
'51 Golden Flash Plunger
'57 Golden Flash Swingarm

Melbourne
The biggest lie I tell myself is
"I don't need to write that down, I'll remember it"

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4528
  • Karma: 41
Re: Timing idler
« Reply #12 on: 13.04. 2014 14:44 »

 I'm hearing you there Bill- even soon's idler comes out, all of a sudden one can't be certain that either mark didn't move just that little bit under (valve) spring pressure or compression ( *ex*was that my imagination *????*, ), unless one was to use temporary marks with marker pen- but unless we're lucky enough the marks are close enough to just spin it a little bit to realign all, I think what I also meant was that if the idler is just replaced as-is, it should takes less than two crank rev.s to bring the Crank and Cam to the right spot, and take the idler out and spin to the marks to check...(better than trying to do eighty or so, as I've tried to do in the past- till I realised the idler had different # of teeth)?

 hope all that makes sense..?? and does it win anything for 'long sentence'- tried to break it up...!

 
Quote
...and will four tanners do  *smile*

 ...four would be fine, but threes' ok take a tip-ple     *beer*
Logged
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia
Pages: [1]   Go Up
« previous next »