1972 cb/cl 100

JB77 said:
Air box came early. No idea when I'll get the boot. It was supposed to be here yesterday. In the attack from the tool box, the air box won.

Yea, my air box won the area by itself too.


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JB77 said:
Air box came early. No idea when I'll get the boot. It was supposed to be here yesterday. In the attack from the tool box, the air box won.

All buttoned up. Still issues half throttle through full. Going to drain and put in New ethanol free gas and see if that is the issue. Other wise back to figuring out jets I guess. I'm real close to just taking it to a shop to see what they think.
Did you put the other carb back on?

Sounds like you and I both are having issues. Maybe these carbs we got are sh1t.

Or maybe...maybe....? ? ? ? ? ? ? ? ? ? ? ? ? ?
No the carb seems fine. I'm just frustrated that with putting the air box and snorkel on it is running the same as it did with the pod. I want it to run like Trek's
Dagnabbit you guys! I will count turns on mine. and pull it off tomorrow and see where the needle is at.

Your bikes ought to be running great. this is the kind of shit that torques me off. When I cant be there and just do it all myself !

Did you guys check timing w a strobe AND make sure it advances smoothly?
You may be surprised how far static time can be off once spinning at speed.

I installed a cheapy ebay digital tach for idle and A/F adjustment. It works...close enough. You have to wait for it when doing A/F because it only updates a change like every 5 seconds or so. runs on its own battery, so only 1 wire to wrap around plug wire as close to the coil as you can.

Hey Trek, how does that tac attach? Seems like a nice affordable thing to have.
I was delayed on working on the 100 yesterday. Wife's rav4 blew a bunch of codes. Ended up needing two new ignition coils and since I was in there and it was recommended, I replaced all six spark plugs. Took over three hours and three hundred in parts, but way cheaper than letting the stealership do it. Had to take the whole air intake system off to get to the backside of the motor where three plugs hide.
Ugh I hate cars. almost wish i was amish.

tach has 1 wire. It works through induction. So, you simply wrap the wire around the spark plug wire as close to coil as you can. 4 or 5 wraps. I taped the wraps to keep it tight on the plug wire. It works good enough...just spits out a number every few seconds.

It can be a little bitch to set up. Its good for 2 or 4 strokes. So, you got to press and hold the buttons then press the button a couple times and get it to scroll to the setting you want. Pain in the butt. but a couple tries and you will get it. Oh and the instructions suck bad too. lol

I had one on my John Deere, it lasted a few years. In the rough conditions. Until Im assuming the built in battery died.

I compared to my high quality analog handheld tach on the crankshaft. it read within 20rpm of that. so its good.
So my timing was a bit off. Still looking to borrow a strobe from someone, but it is running much better and I was able to take it for a quick spin up the road. For all you stock air box guys, what clip are you running the main jet needle? I feel a little popping still around mid to 3/4 throttle so I think I might clip down one to get a bit more fuel in the mix. Currently it is in the stock center clip position.
Oh Im sorry dude. In all the hubub I forgot to reply. Your static setting looks exactly as mine did. I will pop carb off now and check needle.
the needle is in center position.

And on my timing the marks are almost back to being lined up.
Ok, thanks. Can you roll throttle up to full without any hesitation mid throttle?
yes I was actually afraid I was a bit lean. Cause this little thing seems to get hotter than the 360. But, maybe the nature of the beast. I looked at plug while I was pulling carb and my plug is darker (richer) than I care to see. (after normal ride, both high rpm and idle) I dont recall how long I let her idle before shutting down. I may mess w fine tweaking needle a bit once I get tank sealed.

I have not done a single proper chop yet. But I will.

My A/F adjustor is set exactly 1 3/4 turns from bottom.

needle is currently factory set in center groove.

Heres my timing marks after setting w strobe...this does not mean yours will be the same. But, mine was set approx same as yours when static timing was done.
JB77 said:
Ok, thanks. Can you roll throttle up to full without any hesitation mid throttle?

Yes it runs super through out entire range. Also, I do have a brand new stock oiled foam filter from Honda.

Honda part # 17211-107-020
I think I will be ordering a new filter. The box I bought said new filter, but when I opened it up there was a rectangle piece cut out of one side. I thought it was designed that way, but I just looked online, and they are not. At least they are pretty cheap. Going to see if my local shop has one before I go and order one online. Thanks again for all the help trek.
Did you disassemble, clean and lube the advancer w grease? If Im thinking right. It could be reaching max detonation of fuel when piston is too far down on power stroke. ???maybe??? just guessing now. Then maybe w a few more rpm the advancer lurches forward and it clears up by sparking plug where it needs to.


Take it up to where it runs rough. And hold it steady right there for 20-30 seconds. Then chop it and see if plug is light or dark.

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