1978 Express II- No Timing Marks on the Flywheel! Need Help!

[johnny.k]

Hi all,

Been reading the forum here and can't find the information i need to get back on the road. Hope someone can help. I've got a stock 1978 NA50 that i'm trying to get back running. After taking off the flywheel, I've found that there are no visible timing marks. it looks to be stock, with a little bit of corrosion, but not enough to cover any marks. . can anyone tell me to what degree i should be setting my timing? I can use a degree wheel or a dial gauge in the cylinder head to measure position. i read on Dan's Motorcycle magneto timing page that maybe opening at 1.9mm BTDC? Or maybe 20 degrees and 0.14 in.?

is it common to not have timing marks? I've looked all over and wire brushed off the small amount of corrosion, but there is positively nothing there.

i dont want to buy a new flywheel if i i dont have to.

thanks!

johnny

[Ben L.]

From what I understand they have a key and non adjustable timing.

[johnny.k]

First, thanks for taking the time to reapond. Im very new at two stroke operations.

Im sorry, i wasnt clear- or more likely, am lacking understanding.

I can get the flywheel on, but it does not have the "F" or "T" to set the timing

If i know the degree that the "F" is at, relative to TDC, i can set the timing with a protractor.

Likewise, if i know the position of the piston (in onches or mm, measured thru the sparkplug hole) at the time of firing, i can set timing woth a dial gauge.

Am i off base?

Thanks again for your response

Johnny

[johnny.k]

Ok. Maybe my terminology is off. The flywheel goes on just fine. I need to know where the flywhweel/crank/piston assembly
needs to be positioned when i set the point gap since i dont have the "F". The degree on the flywheel where the "F" is. Does that make more sense?

[johnny.k]

Look, i need to set the point gap to .14 thousands. To do so, the flywheel must be aligned to the "F". My flywheel does not have any markings. There is no reason to be obtuse. I only am trying to learn and get my engine running.

How does the key relate to the "F"? Since i dont have any markings, i jave no reference to set the point gap.

[johnny.k]

This is where i am getting my information. I do not have the "F" mark or the "T" index mark. It would be very helpful towards my attempt to get the engine running if someone could provide the angle in degrees between TDC and "F" or the distance between "T" and "F" on the circumference so that i can mark my flywheel and set the points. I can find TDC with a dial gauge. thanks again for your time.

[motormike]

I completely understand your dilema johnny.k...
My internet connection is not suitable to download the manual to check and see if the timing indexes are listed there.
Have you downloaded the Honda Service manual ??
The diagram you posted appears to be from that manual, IDK.

[Ben L.]

Yes you can set point gap but ignition timing is NON ADJUSTABLE.

[johnny.k]

yes, i am trying to set the point gap, but dont have the reference marks. Motor Mike, i copied the picture from the manual. the manual is lacking in detail. i may be able to set the gap by eyeballing when the gap is full open. then setting. i may get close enough to run.

thanks for your response.

johnny

[motormike]

Yes you can set point gap but ignition timing is NON ADJUSTABLE.

According to the diagram in previous post, Ben L., the points plate rotates to adjust the TIME of POINTS opening to coincide with the "F" mark on the flywheel.
While it's true that the flywheel is fixed position by being mounted with a key-way shaft, the TIMING is by all means , adjustable, and changes with the rotation of the points plate.
Good luck johnny.k ...i can see that you have logic and common sense working for you...

[Wheelman-111]

Greetings:

I haven't messed with points since the 1970s, but the Manual diagram shows a test lamp wired between the battery and the (Pulse?) generator. I know your flywheel doesn't have the marks it's supposed to have, but could it be that the light comes on when the crank is in the "Fire" position? Maybe that's close enough.

[wwolvert]

im looking on honda in and its not showing there was a na50 made in 1978 but this is the spec for a 1979 hope this helps you out

Ignition System: Specification

Ignition timing (F mark): 18┬░ BTDC

[johnny.k]

Sorry for the late response, im out of town for work.

I don't have a light, tho i could make one. What i think i will do is go with Dan's magneto timing page and set at 20 degrees. he seems to think it should be close enough....famous last words, right?? I am concerned mostly about burning the piston. i read a few times that too much advance can quickly put a smart hole in the piston top. PS- I understand about not messing with points for a while. last time was a 73 chevy pickup. never messed with two-strokes before so this is a new adventure.

FWIW, i bought this Honda Express II on a whim and have not had this much fun in a long time. must get it running again! Thanks again for all the help.


johnny

[johnny.k]

thanks! '78 was a typo. mine is a 1979, so i was pretty close with 20 degrees.

best news all day! thank you!


johnny

[patthesoundguy]

Is that express 6volt or 12 volt? On my NC50 express bikes I can pull the headlight indicator bulb and socket out of the headlight bucket. I use that for the light bulb. Works perfect and already has the bullet connectors and everything