Hi all,

I hope there is no such thing as a stupid question or two.   I have this project bike and it is the gift that keeps giving but I am determined to carry on.  I had no spark so read as much as I could find on this wonderful forum and had a go.  Spark was eventually there after following the advice and cleaned up the points with contact cleaner and dragging card through. Consistent spark. So all good.

timing came next. Again I had a good read. Head off (another question or two for another night there) dial gauge and looked for 2.9mm btdc timing marks on flywheel and case seemed to match pretty well.  I do have the one year only advance retard spring mechanism that was a bit notchy. I tried to set the points by eye but as mentioned on here it’s a bit hit and miss so decided to remove flywheel and have a good look.  Duly taken off. Cleaned spring up and mechanism and all working smoothly now and can see the cam move on the flywheel assembly. Back to setting the timing..  but of course with the flywheel off there is no cam to open and close the points!
so finally my questions. 

1.  Is there a way to set the timing with the flywheel removed?  Do I have to disassemble the advance/retard mechanism to get at the cam or something or am I just being thick? 

2. I thought I would use the resistance method.  Disconnected the black wire from the stator and used that and a ground on the engine and got a reading of 1.8.  Seemed close enough with the points open.  However, when points closed it was still 1.7/8?

I do have a spark that looks good. But now at a bit of a cul de sac with trying to set the timing accurately.  Do I have to disconnect another wire somewhere to get the 0.4 reading that is in the timing article?

any advice gladly taken on board…. It’s 3.50 am here in the uk. It’s keeping me awake…

many thanks in advance (no timing pun intended)

Morning Ian.

According to the Service Manual (see link), flywheel/rotor should be present. However, maybe if the crank can be turned, other than by using the rotor (eg using the back wheel with bike in gear (a job for Mrs R )), then this might work? I could easily be talking bollox, though!

Vintage Yamaha Enduro Fans - 70-71 RT1 (MX) and RT1-B (MX) Service Manual

Thanks Alan, I can turn the crank when the flywheel is off using the flywheel nut on the crank. But this confirms I need to have the flywheel in situ to get the timing right. So back to square one of points adjustment through flywheel window. Just don’t understand why the resistance is the same with points open and closed with the black wire from rotor disconnected. Just have to do my best by eye. Hopefully get someone on here to tell me I am doing something daft.

Thanks as always. Ian.

If you're using an annologue meter then that's good but the needle movement is minimal & need to watch it closely with a very slow movement over the opening point to see the variation. But i gather you have spark so just mark 2.9mm & with the advance locked full open just let the points lightly touch & tighten the screw. That's in a perfect world but tighten screw & things move. Practice makes perfect. I have a genuine yamaha points checker which is very sensitive with a nearly full needle swing. Not that i ever use it these days.

Many thanks for the info. I will give that a go. My meter is digital now. I used to have a needle one but thought digital was an upgrade. Fool as I am. I should keep an eye out for one

i will have another go today or tomorrow 

cheers

Make sure the analog meter has an Rx1 ohms scale.  Some don't.

One of the best purchases I have ever made was getting a buzz box.... Hook the Red lead to the extra Black wire coming from Stator- Black lead grounded on bike-  find TDC with Dial gauge on Piston- rotate flywheel counter clockwise to desired Timing using dial indicator... then turn on Buzz Box which will produce a steadyTone as long as the points are closed-   now set the points right when the Buzz Box starts to stop with the tone ( meaning points are just starting to open) your good to go...

Also- while your doing this... you can make a Mark on case and Flywheel to reference for TDC mark and the 2.9mm before TDC...  

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In case your looking for them.... this is where I purchased mine.

hvccycle.net/ignition-timing-tester-buzz...3&search_query=buzz+

Thank you sir

I found one on eBay uk for £33 +£3 postage. Arrives Friday hopefully. Will come in handy…

I haven’t confessed on here yet to my two latest Yamaha trail bikes. They are addictive. I haven’t even got partway through this build yet. What is wrong with me?

Tinker Man-  just take your time and enjoy the process for sure and it will all come together.

They are very addictive for sure and the reason most of us on here have a herd of them!