CBX ignition timing

[DENDEN]

HI all,
Hope someone can advise. I have done a complete restoration on a my CBX, excluding rebuilding the bottom end. However, I now realise that the primary chain timing must be one tooth out as I am unable to get the ignition timing correct. I really do not want to strip the crankcases just to correct this timing problem. Could I increase the slotted part of the ignition pick ups back plate to enable me to correct the approx 10 degrees of timing fault?
Any input would be greatly appreciated.

[tevan]

So you split the cases and didn’t get the timing right?

[bobcat]

Oooohhh,aaaghhh DENDEN ! I know it's painful but there's just no substitute
for doing it the right way. You have my sympathy. It's probably only true for me
but when I've made mistakes like that, it usually is an indication or warning that
I've overlooked something else that would have made me have to go back and
correct that too. Maybe someone here knows a shortcut.

[SanDogDewey]

Why would you have to strip the crankcases to get the timing chain correct? Can’t you just loosen the tensioners and put the sprockets where they’re supposed to be? Should be able to do it with the engine tilted.

[aahrens1]

Spend your bike an electronic ignition and your mistake doesn´t matter.
You will have a lot of other advantages like fuel consumption, better starting...

Z66-en.pdf

[daves79x]

Guys - he said he did NOT split the cases. But someone obviously has previously. It's the primary chain timing, not the cam chain timing. The cases have to be split. Yes, it would have been good to check that when you had the top end off and were in the process of rebuilding. Since you didn't split the cases this time, it's obvious someone has and that's a red flag to go in there and check everything. You do not have to remove the top end to correct the primary shaft timing. It's really not that bad of a job.

Dave

[SanDogDewey]

Ah, thanks Dave! Glad I didn’t touch that one.

[DENDEN]

Thanks for all the replies, even tevan who apparently has difficulty reading. If one thinks about it logically the primary chain main purpose is to deliver power to the gearbox. As long as the three ignition pickups can be positioned to achieve the correct timing it should make no difference at all to the advance mechanism or anything else??? Being a very old fart, 79, and averse to hard work, I am going to make a jig to reposition the pickups with about plus 12 degrees. What have I got to lose? Will let you know how it goes.

[tevan]

Thanks for all the replies, even tevan who apparently has difficulty reading. If one thinks about it logically the primary chain main purpose is to deliver power to the gearbox. As long as the three ignition pickups can be positioned to achieve the correct timing it should make no difference at all to the advance mechanism or anything else??? Being a very old fart, 79, and averse to hard work, I am going to make a jig to reposition the pickups with about plus 12 degrees. What have I got to lose? Will let you know how it goes.

I believe you are making a big mistake. If you can’t perform the correct way to fix something why do it. It isn’t that hard to split cases and fix the problem the correct way. You should have checked the timing in the first place before you put a wrench on it. By the way I can read very good and if you would have explained it better I wouldn’t have even committed. I don’t do stuff in a half ass way when I restore bikes and I have done a bunch of them.

[bobcat]

DENDEN, the question needs to be asked "did this problem exist when you bought the bike ?"

[CBX-tras]

There is only one correct way to assemble these motors. Do you not use a factory shop manual?

[DENDEN]

Let me just say again, I did NOT rebuild the lower end of the motor. Yes, I DO always use a shop manual. Yes, I KNOW that things should be done according to the book etc. I was asking what anyone thought about my idea of repositioning the pickups to correct the timing, which, by the way, I have now done, and yes it works fine. Thanks to all those who gave sound advice. To those who where only able to pass comments, rather keep them to yourselves.

[daves79x]

Certainly you can reposition the pick-up plate/pulser units to make everything work. If you keep the bike forever, I guess who cares what the next guy has to scratch head his over. I see this kind of McGyvering all the time. My thought process would be - OK, someone has obviously been into the bottom end before me. If he was this careless about the primary shaft timing, what else was cobbled up? Why were the cases split in the first place? Fixing a hydrolock? That's the most common reason. Did that repair get done correctly?

Those are the questions I'd ask myself, you chose a different path. Good luck!

Dave

[DENDEN]

Hi Dave, Thanks for your response. I agree with you on all counts. However, the motor runs smoothly, oil pressure good, gear box very smooth and clutch and primary not more noisy than normal. The problem is that I am 79 years old and cant handle that kind of heavy work anymore. My latest restoration is a Honda z50a Monkey bike which is more in my range now, mores the pity. I dont intend selling the bike and my son rides it only occasionally and if ever it is sold I will inform the new owner of my gyppo job. Thanks again all.