Timing different from side to side

[SteveD]

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.

I don't think they ship to NA.

[ME 109]

I don't think they ship to NA.

I don't understand why people don't ship to 'wherever the hell it is' they won't ship to.
Joe blow will pay the freight, if he really needs it.
The smart thing to do would be to send the product to joe blow, if he is willing to pay.

It's a bit like some of the super intelligent stores in my town.
When I ask "how long will it take for that to arrive?" I get "oh, er, der, er, about a week, we send an order once a week to reduce the freight cost."
I wait for the 'Ta Dum crash' "but we can have it here tomorrow morning if you want to pay the freight"
But it never comes.

That's why mostly for me it's "hello capital city" I'd like to order XXX.
Their reply is "OK, the soonest we can get that to you is yesterday''
I like it.

[chasbmw]

Motorworks don't sell to the US, they cite insurance liability costs.

However Motobins will sell to the US, and provide by all accounts a fast postal service, get a quote including postage.

WWW.motobins.co.uk

[mattcfish]

Melville,
You've got a bent cam nose, plain and simple. They all bend over time, I think it's heat related. That's what causes the different timing on the cylinders. The cam turns half as fast as the crank, thus you need two points on a lobe for it to fire the cylinders on. If you check again you'll probably notice that both cylinders are in time and out of time depending which stroke they're on. Every other fire (they both fire at once) will be wrong.
Other than bad running, if you had an oil temp gauge on it you'd be amazed at how hot it's probably running. I had a Boyer and a Dyna, neither one could fix this problem. I could move the pick-ups around a little to correct some of it , but not enough. If you mount up a dial indicator on the nose you can measure the deviation. I've heard, a careful tap with a hammer can set it right. The best fix is a crank mounted ignition. Love my Sachse unit.
http://www.elektronik-sachse.de/content ... hp?lang=en
Keep us posted.

[melville]

Melville,
You've got a bent cam nose, plain and simple. They all bend over time, I think it's heat related. That's what causes the different timing on the cylinders. The cam turns half as fast as the crank, thus you need two points on a lobe for it to fire the cylinders on. If you check again you'll probably notice that both cylinders are in time and out of time depending which stroke they're on. Every other fire (they both fire at once) will be wrong.
Other than bad running, if you had an oil temp gauge on it you'd be amazed at how hot it's probably running. I had a Boyer and a Dyna, neither one could fix this problem. I could move the pick-ups around a little to correct some of it , but not enough. If you mount up a dial indicator on the nose you can measure the deviation. I've heard, a careful tap with a hammer can set it right. The best fix is a crank mounted ignition. Love my Sachse unit.
http://www.elektronik-sachse.de/content ... hp?lang=en
Keep us posted.

There we go! I'll give that a shot this weekend. Figuring out how to get the DI to sit still will probably be the biggest challenge.

In a perfect world, I too, would favor a crank-triggered ignition.

[barryh]

Going off at a slight tangent.

While it's only a minor problem, points in a can set ups are not totally immune from timing scatter. On my bean can at least the out rigger bearing plate is not a perfect fit in the end of the can. There is a maybe a thou or two clearance so I centre the end plate with feeler gauges before tightening it down. I've seen the difference this makes when setting the timing.

Whether it makes any practical difference I can't say but as we generally obsess about every other aspect of both cylinders being the same I might as well do it.

[Dan in IL]

Whoa horse! The reason dwell is different between the cylinders is because when you reach top dead center, the cam shaft is pushing on only one set of push rods. The other cylinder has gap in the push rods. When then crank turns 180 d’s the pushing changes sides. This naturally pushes the cam shaft from left to right as the engine turns. It only moves a couple thousandths on an inch but that’s enough to show up on you ignition timing. It’s completely normal for these engines so I don’t think using a hammer is the best fix. Yeah, it might work, but if you break that cam shaft you’ll be crying in your beer that night.
I did get rid of the timing difference with a Dyna ignition unit that I put on the /6 I used to have. I had to work at it, but it can be done.

[Roy Gavin]

Motobins sell the Micro digital for GBP 90- without the coil, and the one I used did even out the firing interval on my 75/7.

Maybe the old non digital version didnt, but it is only $30 cheaper, and not worth bothering about.

[Chuey]

Mellville is a bicycle mechanic among other skills. He won't break his cam nose.

If one did manage to break the teensy fine threaded end of the cam, would a crank fired ignition be a workable fix?

As for the gloves, I have developed a taste for Held gloves and now buy them used. Thing is, evidently, I have longer than normal thumbs and most brands absolutely KILL my right thumb after a ride of any length. Held gloves work in that regard. Plus, all those nail head looking rivets look medieval.

Chuey

[melville]

Thanks for the vote of confidence, Chuey! I should get to it this weekend. "Measure twice, thwack once."