Timing different from side to side

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melville
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Timing different from side to side

Post by melville »

So I had a fabulous ride to SF and back a couple weeks ago, but I had some pinging when climbing grades at freeway speeds in the inland heat. Gave me a good excuse to try some back road alternates to 101 (ooh, that 271!) but this must be fixed. Got home, checked the timing, and it was a trifle advanced, with F sitting high in the window. As my timing plate is all the way retarded, I reset the point gap just a smidge and things were much better. Went on a ride last Wednesday, and had one incident of "pop" as I put a load on it, indicating that the point gap was maybe a wee spot too small for regular use.

So the cover came off again today to see if I could get the point gap and timing to spec at the same time. I cleaned off the points and sanded them flat and shiny, reinstalled and regreased the block, and went about checking the timing statically. I set up my static light and turned the motor over a few times with the wrench in the alternator bolt. I found that consistently one side showed "S" low to below the window and the other side showed it high in the window. I put things a bit more together and used the strobe, revving it slowly up to 3K and saw that I had an "F" that rose in the window and went out of sight as another "F" came into the scene. I may have been pinging on one side only, no?

What is the fix for this with the parts (points, advance unit, cam) on hand? Is this the one electrical problem I can fix with a hammer?
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.
Roy Gavin
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Location: Adelaide Australia

Re: Timing different from side to side

Post by Roy Gavin »

If you look at parts prices the cheapest way of fixing things is a cheap Boyer ignition - they are programmed to fire at equal intervals and you will probably get the bonus of smoother running too.

I fitted one to my 75/7 15 years ago to solve the same problem, and it has been fit and forget - I haven't touched it since.

Boyer also sell kits with matching twin coil and leads for a sensible price, so you can replace the lot at the same time and be certain of getting a result - which suits folks like me who have to order everything from overseas and wait weeks for delivery.
Adelaide, Oz. 77 R75/7. 86 R80 G/S PD, 93 R100 GS, 70 BSA B44 VS ,BMW F650 Classic
dwerbil
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Re: Timing different from side to side

Post by dwerbil »

Roy, is that ignition available in the USA?
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melville
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Re: Timing different from side to side

Post by melville »

dwerbil wrote:Roy, is that ignition available in the USA?
Rocky Point has it, $200. I'm in favor as a next winter project, but I'm under a budget right now. Recent words from the dear Mrs. melville: "You spent HOW MUCH for gloves?!?!?!"

I think I've seen mention of cam nose truing, and I'm ready with all the ugly tools to give it a shot.
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.
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pkboxer
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Re: Timing different from side to side

Post by pkboxer »

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Last edited by pkboxer on Tue May 07, 2013 7:43 am, edited 1 time in total.
'74 - R90/6
Major Softie
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Re: Timing different from side to side

Post by Major Softie »

melville wrote:
Rocky Point has it, $200. I'm in favor as a next winter project, but I'm under a budget right now. Recent words from the dear Mrs. melville: "You spent HOW MUCH for gloves?!?!?!"
Held?
MS - out
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melville
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Re: Timing different from side to side

Post by melville »

Major Softie wrote:
melville wrote:
Rocky Point has it, $200. I'm in favor as a next winter project, but I'm under a budget right now. Recent words from the dear Mrs. melville: "You spent HOW MUCH for gloves?!?!?!"
Held?
Not even! FirstGear, about $60! Therefore the "fix with parts on hand" theme here.
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.
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enigmaT120
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Re: Timing different from side to side

Post by enigmaT120 »

I thought a worn timing chain was supposed to cause mis-matched timing. At least on BMW wasted spark ignitions. My Triumph has two points, independently adjustable. It's such a pain that I have to brag about it.
Ed Miller
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'70 Bonneville
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Major Softie
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Re: Timing different from side to side

Post by Major Softie »

melville wrote:
Major Softie wrote:
melville wrote:
Rocky Point has it, $200. I'm in favor as a next winter project, but I'm under a budget right now. Recent words from the dear Mrs. melville: "You spent HOW MUCH for gloves?!?!?!"
Held?
Not even! FirstGear, about $60! Therefore the "fix with parts on hand" theme here.
Show her this, and it ought to explain how frugal your glove purchase was:

Image

Held Titan
Price: $349.99
MS - out
Roy Gavin
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Location: Adelaide Australia

Re: Timing different from side to side

Post by Roy Gavin »

http://www.motorworks.co.uk/vlive/Shop/ ... M=20&Ct=IA

Cant remember if they ship to the US, but probably dearer than RP after postage.
Adelaide, Oz. 77 R75/7. 86 R80 G/S PD, 93 R100 GS, 70 BSA B44 VS ,BMW F650 Classic
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