Vacuum advance problem

[xsp]

Hi

Been experiencing a mis-fire problem with my 79'E. When looking at the vacuum advance and rev-ing the engine I don't see any movement on the base-plate. Can anyone advise as to how much movement you will see as the revs increase from idle to 4k, if indeed you see it at all?

Any help would be appreciated.

Jonathan
Chester, UK

[81xsproject]

To get answers more efficiently, you may want to add your year and model info to your signature. For instance, the advance/retard units on these bikes from year to year. Some had centrifigal and others are vaccuum.

[GNEPIG]

.. you should see the pic-up coils move alot, take the vac hose off at the carb, then put it in your mouth and suck. it should move and should also hold a vacuum. it is likely that someone else has plugged this vacuum hose onto a vac port on one of the intake boots and not on the number 2 carb port, the intake ports have constant vacuum and the pic-up coils wont move if the hose is plugged onto there, your bike wont run very good either.

[scoobes]

hi if you pm me with your phone number i will try to help you.

[xssiveone]

In addition, try and move the advance by hand. (without the engine running of course!!) They have been known to get a bit of corrosion on the pivot points. Some penetrating oil, and maybe even some lithium grease on the pivots might be needed.

[xsp]

Many thanks for the responses. The bike is a european 1979 E model.

I'll certainly try the 'suck' technique! And make sure the hose is attached to the right connector. I did try moving it by hand and it does move although there is a bit if sticking at first which make prove too much to overcome with the suction. I'll try lubricating the pivot as well.

Thanks again.

[Lamric]

The plate should move until the pickup coil wires straighten out, from memory it's about 30 degrees.

Its a good time to check those wires for worn insulation and breaks inside the insulation (you'll get the 'hour glass' shape when you pull the wire).

[xsp]

Thanks Brian

The pick-up wires do seem to have been replaced at some time and I've tugged them with the engine running with no discernable effect. They're totally wrapped in sticky insulating tape and a bit of a mess so I think as you suggest, it's time to replace them anyway.

[Lamric]

Saw a used set of pickups go for £25 on eBay UK last month when I was swapping mine out.

I've still got the vacuum thingy from the old set if yours is broke.

Yep, never throw anything away !

[xsp]

Thanks for the kind offer Brian. I'll keep you posted on my progress. Hopefully, I'll be able to get out to the garage later (if it stops raining!).

Jonathan

[xsp]

Managed to spend a little time on this.

Double checked that the vacuum pipe was connected to the correct outlet. Was ok.

Tried the 'suck' test to see whether the pickups moved. Even the girlfriend struggled to draw enough to get it to move!

Took the thing off and the plunger is sticking inside the housing....

I guess this item is non-serviceable?

[LoHo]

>Tried the 'suck' test to see whether the pickups moved. Even the girlfriend struggled to draw enough to get it to move!

Hmmm...perhaps you need a bigger hose?
~LoHo~

[Geezer]

Originally posted by xsp
I guess this item is non-serviceable?

And no longer available. You will need to find a used one to replace it.

Geezer