Ignition timeing

[oldman prof]

I have had to replace everything to do with the ignition on the left hand side of the crank and the bike runs but I'd like to know if I have to use a strobe light on the timeing or if there's another way, sorry if it sounds like a stupid question, but its the first bike I've had without points, I would like to get it spot on.

[pggg]

Prof you need the timing light to check, I've seen homemade ones, rigged with brake lightbulbs in the shade, proper brought one's are easier all round

[Geezer]

The light bulb trick is best left to older engines with breaker point ignition.

Spend a few bux and get an inductive pickup timing light. Also I've found that with crappy modern fuels that retarding the ignition a couple degrees makes the bike run better.

Geezer

[TopCatGr58]

Hey Prof,

First, your profile says it's a SPECIAL, but what year, 79, 80, 81 or later? There are differences in the ignitions in the later year models and settings.

Yes, get a light, and put it on the #1 plug wire, that's the farthest left cylinder as you SIT on the bike. Pull the timing cover off, left bottom of engine over crank. This is what you "may" see:


The tang/stationary pointer at the 7 O'clock position is the timing mark, and on the round spinning plate are "C", "T" and "F" marks, you want to observe the "F" mark! The "T" is for TDC, and the "C" is for setting the cam chain tension...see tech tips!

Get engine warmed up, be sure to have box fan blowing against pipes/engine to prevent overheating. Have idle set about 900-1000 rpm, and check to see if the pointer and the "F mark are in line!

The Manual doesn't say to do this with the vacuum advance hose ON OR OFF! It only says that IF the mark isn't aligned, then disconnect and cap off the hose and rev to 5200 rpm, and check the degree at the pointer, for specials, should be 31 degrees.

The 79 and 80 has cent. and vacuum advance components on the timing plate area. The 80 uses special shear off bolt, and "states" that it is NOT adjustable, but you can replace them with reusable bolts...this may also be a USA emissions thing, and may not apply to yours.

The 81 unit ONLY has Vacuum advance unit, the Cent. curve is built into the TCI. The 82XJ has neither cent. or vac. modules on the timing plate, they are incorporated into the TCI with use of a special vacuum sensor box!
T.C.

[oldman prof]

TopCat, in that reply you've told me more than I've found out here in the approx. 2 mnths I've had the bike,I see I've come to the right place,Ok, as far as I know it is a "81" and the smashed parts I took off had no centrifical advance unit(I think thats the cent you are talking about) I just thought the idiot who had the bike lost it in the accident,I have both in now and it seems to run well enough,but it starts a bit hard (a lot of swinging) untill it's warm,but I just put it down to timeing that was out.Please advise on my next move,I just hope I hav'nt damaged anything up to now.I bought the bike for R2500 which is about 20 pounds in your money more or less so you see thats very cheap to me so I do'nt mind spending money on it,I intend to keep it for the long road, so it must be reliable and I hear that it is,I still have my sohc 750 honda for around town but she's getting a bit tired now.
Thanks
Anthony

[oldman prof]

Originally posted by oldman prof
TopCat, in that reply you've told me more than I've found out here in the approx. 2 mnths I've had the bike,I see I've come to the right place,Ok, as far as I know it is a "81" and the smashed parts I took off had no centrifical advance unit(I think thats the cent you are talking about) I just thought the idiot who had the bike lost it in the accident,I have both in now and it seems to run well enough,but it starts a bit hard (a lot of swinging) untill it's warm,but I just put it down to timeing that was out.Please advise on my next move,I just hope I hav'nt damaged anything up to now.I bought the bike for R2500 which is about 20 pounds in your money more or less so you see thats very cheap to me so I do'nt mind spending money on it,I intend to keep it for the long road, so it must be reliable and I hear that it is,I still have my sohc 750 honda for around town but she's getting a bit tired now.
Thanks
Anthony

sorry me again,just to confirm my info:I set no.1 at tdc then line up the pointer to the "t" mark to get it in the right place then start from there with the strobe???

[pggg]

Prof, hook the light to battery and No1 spark wire. Start bike, let it idle , shine the strobe at the spinning plate, there's the marks, idle is f, about 30 to 35 degrees when revving high and no vac hose attached, don't remember whether the idle marks change with/without the vac hose, if they do, it won't be much, but without the vac hose the timing gets up high, about 50 degrees on the spinning plate, don't know if that's the same with load on the motor or not

[oldman prof]

Thanks pggg now do I have to remove the mechanical advance unit or can I leave it there,I think I can find the old one,but just in case??

[randy]

prof,

If your igntion controller (TCI) has a model # on it that starts with 2H7, then you need the mechanical advancer.

If the TCI model # starts with 4RO, then you don't need the mechanical advancer.

[TopCatGr58]

Hey Anthony,

Like Randy said, if you truly have an 81 with the 4RO TCI, it'll be labelled on it, then you don't need the mech. cent. advance parts. You said your old 81 parts were smashed, so I wouldn't want to put those back on!

A few options. The 81 TCI is a bit rare(only made 1 year) and you could get a decent price for it. The previous 2H7 TCI is more common(3 years produced), and combined with the mech. cent. and vac. advance unit/parts is easier to find/repair/ or even replace with other options.

There is a tech tip....scroll down from the MAIN FORUM PAGE, not the links in the left column, and look for MODS, Electrical and you should find one about replacing the TCI for the 78-80 series with components from automotive parts!

You might look into your local area for finding a 2H7 TCI and how much it would cost as well as what you could get for the 81TCI!

Glad to be of service, that's what we're here for!

PS, try reading the other tech tips while you're there, will help you with the delicate cam chain tensioner procedure and such!
T.C.

[oldman prof]

Hey guys you've got me by the short & curlys here, what happend to the time all you needed points condencer ,coil(s),plugs to burn fuel,ok where will I find ignition controller(tci),I prob'ly seen it but don't know its name or I know it by another name,exactly were is it and what does it look like.
Now lets get to the parts I do know,I went back to the parts I took off the bike,the vac. advance diaphram ass'y was ground away and one of the pulser coils looks damaged,will test it tomorrow,every thing else can be used,are all the pulser interchangeable

[randy]

OK,

If you've got an '81, the TCI is under the seat, a 4" X 5" box.

For pictures, click on my www above and go to the "TCI repairs" page.

[edgo]

While you have the cover off replace those phillips screws with hex head bolts. They make the job easier.

ED

[oldman prof]

Yes yes I know the box we call that a CDI unit or box it has no foil on it but you can see something was stuck there I'll have a good look at it when I come home from work tomorrow,its a bit cold and wet outside at the moment,at least I feel I'm starting to understand a lot more thanks to your help.
Thanks again,I'll be back when I've got more info.
Anthony

[oldman prof]

Ok I sorted out the tci now I just need to know why my bike has no oil cooler, did somebody take it off,or did'nt it have one