Cold front cylinder

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benshannon
Posts: 46
Joined: 12 Feb 2014 12:16
Location: leicestershire

Cold front cylinder

Post by benshannon »

So, a couple of times now the rev counter stops working and I lose alot of power. I can just about limp home. Some times I find the rev counter works but the front cylinder is mostly cold with a little bit of warmth at random intervals. The rear is always warm.

I switched transducers over but the fault didn't move over. I switched plugs over, still the same. (I have ordered new plugs to try)

Carbs are clean, it isn't a fueling issue.

So, I'm thinking it could be pick up.

So, how do I test the pick up to rule that out?
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Ming
Posts: 798
Joined: 01 Aug 2014 16:32
Location: France
Location: Central France

Re: Cold front cylinder

Post by Ming »

Is that an electronic or mechanical rev counter?
benshannon
Posts: 46
Joined: 12 Feb 2014 12:16
Location: leicestershire

Re: Cold front cylinder

Post by benshannon »

Electronic mate.
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Ming
Posts: 798
Joined: 01 Aug 2014 16:32
Location: France
Location: Central France

Re: Cold front cylinder

Post by Ming »

I have known the tacho 'die' if the battery loses charge, but I don't see how that could affect the ignition. Paul Compton and Soren Hansen have clips on You tube which show how to test the various components in the ignition system.
stradella
Posts: 28
Joined: 04 Dec 2019 23:46
Location: Melbourne Australia

Re: Cold front cylinder

Post by stradella »

A long time ago my 500 started to run on one cylinder only. There was a very fine crack in the black resin material in the pick-up - which must have broken an embedded component. If you have another pick-up (known to be good) you could fit it to see if that is the answer. Or you could remove the rotor to have a good look at the resin material. Even better might be to remove the pick-up and then you might be more able to see any crack/s in it.
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: Cold front cylinder

Post by MickeyMoto »

As you know the transducers work, take out the plugs, stick them in the caps, lay them on the cylinder heads and kick or use the electric start. You should have a spark on the rear plug only. Swap the red wires on the transducers and repeat the exercise. Does the other plug spark?

Does this sound right?
mbmm350s
Posts: 666
Joined: 22 Jun 2018 10:18
Location: Reading UK
Location: Berkshire UK

Re: Cold front cylinder

Post by mbmm350s »

@Mickey moto. Spot on.
Often the pickup works when cold. Next to try with a heat gun gently or when it has failed out on the road.
As another poster says look for tiny crack in the resin use talc to make it visible. Pickups can be repaired ask George Lane on Facebook page. Alternatively there are reproduction parts from Nuovaray in Italy or Marcus Hellig in Germany. The ultimate solution is to replace everything with the digital sachse system but this is much more expensive.
Mark.
Bruce3500
Posts: 20
Joined: 13 Apr 2020 05:57
Location: Eastbourne

Re: Cold front cylinder

Post by Bruce3500 »

I had this years ago with my sport, front cylinder dropping in and out, found to be faulty pick up, fitted new one and fault was cured, if i remember there is a test proceedure in manual, hope this of use
Kamel
Posts: 175
Joined: 10 Feb 2020 22:31
Location: Zurich, Switzerland

Re: Cold front cylinder

Post by Kamel »

mbmm350s wrote:@Mickey moto. Spot on.
Often the pickup works when cold. Next to try with a heat gun gently or when it has failed out on the road.
As another poster says look for tiny crack in the resin use talc to make it visible. Pickups can be repaired ask George Lane on Facebook page. Alternatively there are reproduction parts from Nuovaray in Italy or Marcus Hellig in Germany. The ultimate solution is to replace everything with the digital sachse system but this is much more expensive.
Mark.
Mark, if you join the Sachse "group buy" I've arranged you will get a 10% discount as we already have 5 confirmed buyers. If we can get up to 10 or more there will be another 5% knocked off. And don't forget you should be able to sell on any good parts to soften the blow.

http://www.morini-riders-club.com/forum ... f=4&t=6323

Cheers,

Kamel.
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