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timing and points


bondy
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Perfect description of how to set points on these bikes. If you can do em on the bultaco you can set timing on anything. My only suggestion is the use of a seperate flywheel to set the ignition. Only problem with that is the points cam on the inside of the flywheel can wear at different rates from flywheel to flywheel so best to use the one you are going to run with when setting up points

Steve

Steve,

i agree with that, but with my mr magoo eyesight and sausage fingers, trying to set the points through the window is a no no. but to be fair i have used the same cam on both a model 92 and a 198A engine with perfect results. must of just hit it lucky i guess. the use of the micrometer timing tool helps a great deal as well. worth splashing out on one of these.

Tom,

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  • 11 months later...

Hello mate,

firstly you have to set the correct gap at the points, which is 0.35 to 0.45mm or 0.013 to 0.017 in old money. Bit fiddly this bit, as you only have the little window in the flywheel to work through, unless you have an old flywheel that you can take apart and just use the cam. i will assume that you dont have this luxury. you adjust the points through the window using 2 small screwdrivers and a set of feeler gauges set within the tolerences above. i find 0.40mm works for me. turn the flywheel by hand so that the points are fully open. check the gap. adust the gap by slightly undoing the larger of the 2 screws on the points. with another screwdriver turn the smaller screw to adjust the gap in the points. the feeler gauge should slightly drag on the face of the points. remove the feeler gauge still maintaining the points gap by holding the small screw with a screw driver. using another screwdriver do up the larger screw and recheck the points gap. most probably find the gap is incorrect, if its within the tolerences above ok, if not try adjusting again, will take a few stabs to get it right, stick with it as this needs to be bang on, to be able to set the timing. next thing is to set the timing which is 2.8mm to 3.00mm before top dead centre (BTDC) this is where the piston needs to be in the barrel when the points are closing. to get this measurement you will need a timing tool. these are cheap and can be got from bultaco uk or sammy millers. i have a micrometer timing tool which is a little more expensive but more accurate. (1) take out the spark plug and insert the timing tool finger tight. turn the flywheel by hand so that the piston pushes the plunger in the tool to furthest it will go before dropping down again. this is the top dead centre of the pistons stroke.(2) turn the flywheel counterclock wise slowly untill the plunger in the tool has dropped 2.8mm to 3.0mm this is when the points should be starting to seperate. to check this with any accuracy, you need to use an ammeter or a simple tester. you can make one by wiring a bulb and battery in series and connect the wires to the black and red wires coming out of the stator. really is worth making one of these or buying an ammeter. make sure the ammeter has an audible continuity facility and crocodile clips. assuming you have a wired bulb.(3) turn the flywheel so that the bulb just goes out. check the measurement on the plunger if its within the tolerences great, if not then the timing need to be adjusted. (4) take the flywheel off. slacken off the 3 screws holding the stator plate in position. (5) Turn the stator clockwise to advance the timing or couter clockwise to retard the timing. you only need to move it slightly, tighten the 3 screws. (6) replace the flywheel (make sure that the flywheel is fully on the shaft) i put the nut back on and do it up. Repeat 1 through to 3 to check that it is correct. If it is, great, tighten the fly wheel fully and remove the tool from the spark plug hole. if not correct then repeat the process. dont worry mate if you are gonna own a bully for a while you will get quite expert at this. But seriously, scour fleabay, auto jumbles for another flywheel that you can take the centre out of by drilling the rivets out. makes the whole process a piece of cake. Stick with it and hope that this helps, it works for me, my 198 starts within 3 kicks. you could do away with all this and go for an electronic ignition with the added bonus of a massive spark. i have re-read this a couple of times and think that i have listed everything. i am sure the more experienced bultaco guys in here may have a better process.

Good luck,

Tom,

Thanks for from Tom - very useful. I have a 325 199 and have trouble getting to run right. I have wired up a test circuit as advised and have found TDC using a measure in the spark plug from Bultaco. in order to get the light to turn on anywhere near 3mm I have to turn the rotor clockwise - Tom says turn anti-clockwise. Given that the crank and rotor spin anti-clockwise doesn't this move me towards After top dead centre?

If i move clockwise the light doesn't come on until approx 12mm later. I'm confused!

I do have a problem in that my stator plate is fully advanved (clockwise) and have been advised to set points at a non standard gap (new points from bultaco) and then try to find 2.75mm BTC

Any advice gratefully received as this bike has been ages being refurbed and I am itching to ride...

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I probably messed up my first posting - hence trying again.

I have tried to follow Tom advice - only in order to get my timing light to come on anywhere near 3mm (after finding TDC using a spark plug guage) I have to turn the rotor clockwise. Tom advises ani-clockwise. Given that the crank rotates anti-clockwise isn't this taking me to after TDC? If I do turn anti-clockwise the light does not come on until 12mm later.

I do have a problem in that the stator plate is fully advanced, which must be wrong. As I say turning the rotor back clockwise will get me to 3mm but no less. I am using new points from Bultaco. Advice has been given to change the gap to get the light to come on 2.75mm with the stator plate in its original position (which was just in advance of centralised).

Any advice greatly received as I do not jknow whether i am going backwards or forwards and am mightily confused!

Mudferret

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Hello Mudferret. What you do is with the dial gauge or TDC gauge is have it at top dead centre and zero it then move the flywheel to about 4mm past TDC in a clockwise direction then come back anticlockwise until you hit 2.75mm BTDC or at whatever timing you have chosen to use. I hope this helps. Bully Lover.

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  • 8 months later...

hi just to let you all know it was the magneto that was the problem i was lucky i had a spare magneto tryed it whent on no problem. turns out the inside off some magnetos have a steaper angal than others so that was the problem.

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Did mine today for the first time.

I followed Toms excellent instructions above - having read the other thread as well.

After fitting new points, condenser and HT coil, I struggled a bit with the points gap as the tapered sections on all my feeler gauge sets are too wide to fit through the window and reach the points! Managed it in the end by butchering/adapting a set.

I set the timing using the simple TDC gauge, not a vernier one, being careful to rock the piston back and forth through TDC so that I got the exact point. I then marked it by pulling the plunger out and sticking a sliver of masking tape on it, dropping it back in and repeating and adjusting until the top of the tape was level with the holder top at TDC. Viewing from the same angle by making sure I looked straight across the top of the holder. I then carefully measured and stuck another piece of masking tape on the plunger so that the gap between the two was 2.5 + a bit mm. I used my multimeter as a buzz box between the black wire and earth to get the timing right. Must have had the flywheel on and off 10 times.

From being a reluctant sod with an intermittent spark, the bike now starts second kick every time and sounds fine.

Lesson learnt - get an old flywheel and chop the centre out. It must make life so easy!

Henry

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henry all my bikes are sorted they all run spot on. i was just gathring info so if i ever have to do it i know were to start. if i can do it then id run them on points all the time as they should be. but just keep a eletrice iginiton in my tool bag for a back up

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Lesson learnt - get an old flywheel and chop the centre out. It must make life so easy!

A potential problem there is that the cam may have worn differently on the flywheel you butcher so that the points gap is different when you put your own back on. Probably not enough to make any significant difference but with the luck I have it would be...

Edited by woody
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  • 2 years later...

Hi I am a new member to this site and need some advice on setting my points ignition timing on my 1976 350 sherpa.after reading above thread from mudferret posted in 2012 I have exactly the same problem with my timing when I set timing to 3 mm btdc my stator is fully advanced (fully clockwise) with no more slot to adjust further I am aiming to achieve 2.75 mm btdc so I don't get why the stator is this far advanced all ready.I am using Tdc plug gauge and I have a test light to check when points are breaking I also have the centre out of a spare flywheel to aid in points setting.if anyone has advice it would be appreciated I am pulling my hair out.

Regards Darren

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Hi I am a new member to this site and need some advice on setting my points ignition timing on my 1976 350 sherpa.after reading above thread from mudferret posted in 2012 I have exactly the same problem with my timing when I set timing to 3 mm btdc my stator is fully advanced (fully clockwise) with no more slot to adjust further I am aiming to achieve 2.75 mm btdc so I don't get why the stator is this far advanced all ready.I am using Tdc plug gauge and I have a test light to check when points are breaking I also have the centre out of a spare flywheel to aid in points setting.if anyone has advice it would be appreciated I am pulling my hair out.

Regards Darren

Why do you worry about the difference between 2.75 and 3mm. These bikes have engines that run on a setting between 5 mm and 2mm before Tdc. Today at a trial my friend had ignition woes... Turned out the condensor was toast. The points were badly pitted, I took some sand paper to them,(not ideal, but it was all I had in the van). After cleaning them up and changing the condensor he reassembled the ignition without even checking the timing and it ran fine... You don't need the ignition on these bikes set spot on to run. Are the points new or is the lifter that runs on the cam worn?
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Hi I am a new member to this site and need some advice on setting my points ignition timing on my 1976 350 sherpa.after reading above thread from mudferret posted in 2012 I have exactly the same problem with my timing when I set timing to 3 mm btdc my stator is fully advanced (fully clockwise) with no more slot to adjust further I am aiming to achieve 2.75 mm btdc so I don't get why the stator is this far advanced all ready.I am using Tdc plug gauge and I have a test light to check when points are breaking I also have the centre out of a spare flywheel to aid in points setting.if anyone has advice it would be appreciated I am pulling my hair out.

Regards Darren

I also wouldn't worry too much about the 0.25mm.
But there's no harm in filing the slots out a bit to get the desired adjustment i.m.o.
Check first if the flywheel sits perfect on the key of the crank shaft.
If all else fails you can use one of these bolts:
SPECIALIST_BOLTS_CHART_1AD63869-979D-8DC
Edited by guys
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