Author Topic: Starting the engine (Read 42198 times)

El__burro · « **Reply #45 on:** January 20, 2015, 05:28:51 PM »

Some more sparks. Unfortunately I am at the end of the plate. Can't push it more anticlockwise. Still points start opening just after the F mark has passed the peephole. Points fully open when T is in the peephole. Tomorrow I'll remove the plate to check the spark advancer. Yet i don't know what to look for.
Thanks
El__burro

El__burro · « **Reply #46 on:** January 20, 2015, 05:29:34 PM »

Mike, what do you mean?

hairygit · « **Reply #47 on:** January 20, 2015, 05:35:59 PM »

El Burro, I take it you are using decent condition points, ie, the heel part that contacts the cam aren't worn down/shagged, because you'll never get it right if that's the case, a lot of pattern ones have heels not much harder than chocolate:'(

royhall · « **Reply #48 on:** January 20, 2015, 05:37:58 PM »

Once you take the back plate off (3 screws) you will see the advancer mechanism. Try moving it by hand, the weighted ends should move outwards freely and drop back when you let go. If they dont, free them up with some WD40 and try again.

There is some reason you cannot get the timing on the correct mark. Of course when you find it, it will be obvious. Got to find it first though. Good luck, and try not to get too frustrated. The answer will be right there in front of you somewhere?

mike the bike · « **Reply #49 on:** January 20, 2015, 06:35:38 PM »

Quote from: El__burro on January 20, 2015, 05:29:34 PM

Mike, what do you mean?

The points cam fits over the advance retard mech. The bob weights fit into a slot either side of the cam.
When the engine is revved, the bob weights expand and the lugs on the weights rotate the cam slightly.
It's possible to fit this cam backwards, which leads to a lot of head scratching.

Bitsa (Ralph Wright - RIP) · « **Reply #50 on:** January 20, 2015, 06:52:14 PM »

Take no 1 cylinder tappet covers off.Turn engine and watch the inlet go down and then back up.As it comes to fully closed the F mark for 1-4 the points should just start to open.If not the gap is set to small or advance is 180 out.Same goes for 2-3.
Cheers
Bitsa

K2-K6 · « **Reply #51 on:** January 20, 2015, 11:16:55 PM »

You could try disconecting the wires from the points into the loom and then continuity checking each one down to earth while you rotate the crank to see if they are actually switching on and off as they should do (points closed=connected to earth, points open=contunuity interupted) if they don't then it's possible one of the insulation washers where the wire connects to the points is missing and leaving the wire connected to earth all the time.

Lobo · « **Reply #52 on:** January 21, 2015, 04:46:13 AM »

... some good tips coming through.. some background reading that I've found below.

http://forums.sohc4.net/index.php?topic=73769.0

http://www.hondachopper.com/garage/carb_info/timing/Static_and_Strobe_Timing.pdf

K2-K6 mentioned those insulation washers... pictured clearly below.

hairygit's (worn heel suggestion) .... points are cheap... tho' often too cheap, so replace with good quality ones..... cue... Bitsa!
Furthermore... is the whole backplate assembly OEM / quality ... as suggested in the above forum thread... maybe this is your problem... eg adjustment slots incorrectly placed.

IF you don't have fag paper, Ka-Ja & K2-K6 suggest use your multimeter to confirm exact points opening time... see red carpet pic below ... & connect one end to the Blue lead (cylinders 1/4) and the second to earth (ie the back plate), and as the mark sweeps (clockwise) past the F that point should open & the meter's needle fall away as the circuit goes 'open'. Later repeat for the Yellow (2/3 cylinders) and earth. (set your meter to the same scale as you did testing the primary (4.4 ohm) coil winding... and disconnect the points Blue / Yellows from the coils for this set-up routine)

The advance retard...since you seem a bit vague on this assume you've never had it apart... and also that you've never seen the bike running? (if you have seen it running I'd leave it be ...., if not possibly the answer). However, pic attached - bottom pic nicely shows the cam (which freely rotates about its centre spindle) .... which might have been put on upside down! If so, you'll have to remove the springs, remove the two circlips, then the 2 flyweights & finally the cam before replacing it 'the right side up'. Fiddely...

Finally, if it's your intention to strip / restore the bike.... is this all worth it?

Your weekend shaping up nicely....

Simon

royhall · « **Reply #53 on:** January 21, 2015, 08:59:46 AM »

Keep it simple guys. He says he cannot get the points to open on the correct mark, but has seen some sparks at the plugs. That's mechanical surely. Weak spark as the points are only just opening. Knackered points, stuck advancer, points cam on wrongly (not sure how that works though as its pegged), points gap wrong. The problem is around the points plate somewhere. Cheers all.

El__burro · « **Reply #54 on:** January 21, 2015, 10:03:32 AM »

I'll concentrate my efforts on the advancer, yet the all area where the points plate seat and also some of the plate is a bit damaged. No big deal though as all the bits are there.
I've attached a picture of the points, the plate and the housing.
I have also removed the advancer and seems fine. How do I remove the bolt that holds it?
Also how do I check if the part mentioned above is fitted 180 degree out?
Thank you all very much for your suggestions

El__burro

ka-ja · « **Reply #55 on:** January 21, 2015, 10:59:52 AM »

Hi,
I think you need help from some-one with good mechanical knowledge, the"bolt" that holds the advance/retard looks to have the head sheared off, is it seized in the crankshaft?----Ken
PS see if the unit will pull off the crankshaft and take another picture!

El__burro · « **Reply #56 on:** January 21, 2015, 11:09:04 AM »

Thanks, the tread is fine, how do i take it out, just pull?

Johnwebley · « **Reply #57 on:** January 21, 2015, 11:14:44 AM »

the small center bolt is threaded,suggest you undo carefully with mole grips,if it is tight use plenty of penetrating fluid

ka-ja · « **Reply #58 on:** January 21, 2015, 11:16:15 AM »

Hi,
The unit should pull off the crankshaft, it sits on the end of the crankshaft on a locating peg, the "bolt" sticking out the middle should screw out, but it is minus its head for some reason!---Ken

El__burro · « **Reply #59 on:** January 21, 2015, 11:25:14 AM »

Not sure if i am going crazy but..
In the picture below there is my advancer against a picture of the one Lobo send me.
The mark on it (highlighted in red) is pointing to F2.3 on mine and to F1.4 in his.
Does this matter?

Thanks
El__burro

Honda-SOHC

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