Author Topic: 1974 CL 125 "Lil Frank" I cant leave anything alone!  (Read 40424 times)

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Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #50 on: September 14, 2010, 09:25:53 PM »
Took it out for a couple mile ride. It idles ok but when it is just sitting there idling it is not constant. It goes up and then drops then goes up again. Not a lot just a few rpms. If i had to guess it surges between 1100 and 1300. Any idea what causes this? Carbs or timing? Also when i get it up to speed and im just maintaining speed it lurches. Like its missing a beat and losses power. Anybody know theses symptoms?

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #51 on: September 15, 2010, 04:02:01 PM »
Took the bike around the block and it was still running funny. so i started messing with the timing and then things all went to #$%*t. So i pretty sure that it is a ignition type problem and not carbs. I ordered points and condensor so we will see if that fixes anything. The motor makes a funny "zzzzzzz" noise from the top end when it revs down. Could it be the cam chain? The manual says tighten the chain till you feel tension but i backed the screw out pretty far and it never really felt significant tension.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #52 on: September 24, 2010, 03:31:49 PM »
New points and condensor and spark plug are in today. Got it to run. Yeah! now i cant get the thing to idle right. It keeps getting hung up at a high rpm and will drop if i put the bike under load. Any idea? Where should i start? Re adjust the valves or should i go after the float height?

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #53 on: September 24, 2010, 07:16:04 PM »
Pulled the plug and its black and sooty. My theory is that the float is to high and its running to rich.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #54 on: September 24, 2010, 07:18:43 PM »
Just talking to myself here i guess. :( Adjusted the float level from .944 inches to 1.07 and now it idles pretty good. Ill fire it up in the morning to see if it still is good. It still surges when im at cruising speed. Cant figure out what that is.

Offline Shenanigans

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Re: 1974 CL 125 "Lil Frank"
« Reply #55 on: September 24, 2010, 07:40:43 PM »
Just talking to myself here i guess. :( Adjusted the float level from .944 inches to 1.07 and now it idles pretty good. Ill fire it up in the morning to see if it still is good. It still surges when im at cruising speed. Cant figure out what that is.

Sometimes that is the only thing that helps!


I have that same motor in a 1970 SL frame. I have done HORRIBLE things to that motor and it still ran. I rode it out to a town 20 miles south on the freeway. Gear for the dirt, it took about 2 miles to get up to a wopping top speed of 53. I forget at what it redlines  but I was about 2 grand above that for a straight 45 mins. each way.
« Last Edit: September 24, 2010, 07:44:58 PM by Shenanigans »
   This pretty much sums it up.   76' CB592 cafe. 69 750 project, 03 CBR954, 75 750 super sport.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #56 on: September 25, 2010, 09:05:00 PM »
Took the bike out for a spin today and it ran pretty good. Tightened up the chain and the surging is better, I think... I dont need the choke to get the bike started so im thinking it might be a little rich still. Ill pull the plug and see what its looking like now.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #57 on: September 27, 2010, 04:25:57 PM »
Moved the flaot level to 1.17 now. Running a little better but still surges a little. I think im going to recheck the valves. Also the bike dies when i use the blinkers... Not sure what thats all about but i might try a new battery.

Offline hoodellyhoo

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Re: 1974 CL 125 "Lil Frank"
« Reply #58 on: September 27, 2010, 05:09:21 PM »
From what I have learned here surging is usually a carb/intake issue.
1972 CB350F (Back from the Dead!)- http://forums.sohc4.net/index.php?topic=20822.0
1965? S65 - Coming Eventually!
1972 CB750K2 (father-son project)
1976 CB750K6- (sold) http://forums.sohc4.net/index.php?topic=96859.0
1976 CB750K6 (sold)- http://forums.sohc4.net/index.php?topic=62569.0

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #59 on: September 27, 2010, 05:39:10 PM »
thats what i thought but i have a stock setup and a very clean carb. My thinking is that its maybe a combination of the intake valve and the timing advancer. Or that the low battery is not giving it enough spark at that RPM. Not sure but im going to get a battery right now and hope that will at least fix the blinker issue if not the surging as well.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #60 on: September 27, 2010, 07:03:19 PM »
Ok have to wait on a battery. The shop was closed. I think the blinkers are shorting the system out somehow. Also the bike runs fine and will idle but when you slow down to a stop sign and brake it will die. Frustrating little bike.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #61 on: November 24, 2010, 02:14:25 PM »
Just a little update. Got the bike running pretty good. I also picked up a parts bike, its a cb100 but they are pretty much the same. I swaped on the exhaust so i can get a set of CB125 side covers now. I took the rack off and added the center stand from the other bike. I think im going to put the forks from the 100 onto the 125. This bike is going to be slowly cafed. When i put the new forks on it will get a pair of old clubmans  i have lying around. The seat pan off the 100 is going to be the base of the cafe seat, if its not to rusty.


Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #62 on: November 29, 2010, 09:57:22 PM »
ANybody following this thread know how to separate the fork uppers and lowers? There is a screw in the bottom just like the 550/750 forks but it just spins. the tube is to small to stuff a broom stick or anything else down. I read the manual and the parts diagram doesnt even show the screw.

Offline jaguar

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Re: 1974 CL 125 "Lil Frank"
« Reply #63 on: November 30, 2010, 04:33:09 AM »
Try pulling down on the lowers while you turn that screw

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #64 on: November 30, 2010, 08:33:24 AM »
i tried that and all it does is spin free. If i push the lowers all the way up i can feel a little resistance but its not grabbing enough for the screw to break free. And now the fork oil leaks out the screw so i cant just refill it and leave it alone.

F!

Offline jaguar

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Re: 1974 CL 125 "Lil Frank"
« Reply #65 on: November 30, 2010, 10:11:06 AM »
Is the top nut still on?

Offline HalfFastMoto

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Re: 1974 CL 125 "Lil Frank"
« Reply #66 on: November 30, 2010, 10:45:05 AM »
ANybody following this thread know how to separate the fork uppers and lowers? There is a screw in the bottom just like the 550/750 forks but it just spins. the tube is to small to stuff a broom stick or anything else down. I read the manual and the parts diagram doesnt even show the screw.

An approach that I've used for years with great success is to leave the fork fully assembled, in the triple with wheel attached.  I use a ratchet strap to fully compress the forks and then I use my 1/2" air gun with allen head socket to loosen the damper bolts.

Works every time no matter how crusty the forks are!   ;D
-brad

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The appropriate number of bikes is "1" more!

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #67 on: November 30, 2010, 11:55:41 AM »
Yeah, im pretty pro at taking apart the 550/750 forks but apparently these are different. I eventual stripped the bolt so i sad F it. These are off a parts bike and ill just reuse the ones on the bike. So i drilled out the bolt and yanked the forks apart. Only to find out that all you really have to do is YANK!. Once you remove the cir clip that holds the rubber seal in you just yank on the fork a few times and it comes apart. the bolt in the bottom is not supposed to come out! Oh well, live and learn. So now i have 3 front forks instead of 4. :-\

Offline HalfFastMoto

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Re: 1974 CL 125 "Lil Frank"
« Reply #68 on: November 30, 2010, 12:15:11 PM »
the bolt in the bottom is not supposed to come out!

Pics pls - I've done a lot of forks and have yet to see this issue   ???
-brad

Better HalfFast than HalfA$$ed
The appropriate number of bikes is "1" more!

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #69 on: November 30, 2010, 08:44:42 PM »
Picture could not even explain these forks. All i can say is that the bottom bolt does not come out. On other forks that bottom bolt is what keeps the fork bottom from sliding off. Well on these, there is a cir clip under the fork seal that keeps it from sliding off. So once the clip above the seal is off you just yank on the fork and it drives the seal out from the inside.

So i took the forks off the running bike and the tubes are shot. The ones off the spare bike are OK but im not about to spend $140 on forks for this one so it will get the best tubes of the 4 i have.

I drilled a set of clubmans and ran the switch wires through. HOLY CRAP that is one of the most trying jobs ever. Clubmans are almost impossible to run wires through. Let alone 8 of them on 1 side. But i got it done.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #70 on: November 30, 2010, 09:15:40 PM »


Ok this is the part that the screw goes into. It sits at the bottom of the fork lower, just like this and the (phillips) screw goes into it holding it down. Thats it. Kinda confusing but if anybody is ever rebuilding the forks on a CB100, CB125, DO NOT F WITH THE SCREW!


Hours of Work! and i forgot to put on the brake perch before i ran the wires so now i have to buy one that i can bolt on after. I am not pulling those wires again.

Offline HalfFastMoto

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Re: 1974 CL 125 "Lil Frank"
« Reply #71 on: December 01, 2010, 08:08:39 AM »
Interesting - now that I think about it I don't remember ever changing fork seals on an externally sprung fork.  I'm looking at the schematic of BikeBandit and it has me wondering -  http://www.bikebandit.com/assets/schematics/Honda/HJ0906W0124009.gif 

It looks like the piston is affixed to the outside of the fork tube and I don't see a damper rod, are the damping ports integrated into the fork tube?    ???
-brad

Better HalfFast than HalfA$$ed
The appropriate number of bikes is "1" more!

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #72 on: December 01, 2010, 09:34:54 AM »
Yeah there are , I think 4, holes in the bottom 6 inches of the tube.

Offline Flying J

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Re: 1974 CL 125 "Lil Frank"
« Reply #73 on: December 01, 2010, 09:30:41 PM »
Well got the forks rebuilt just need to add oil. Re painted the headlight and re ran all the wires. Hooked all the cables back up. Going to have to order some new ones. The 36 year old cables dont bend so well. It still doesnt look right to me. I think it needs a cafe seat and shorter fender. What do you think?

« Last Edit: December 06, 2010, 05:18:41 PM by ffjmoore »

Offline Flying J

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Re: 1974 CL 125 "Lil Frank" I cant leave anything alone!
« Reply #74 on: December 06, 2010, 05:25:54 PM »


I dropped the front of the tank an inch. Can you tell? I can. now when i do a new seat i can have that nice straight line from the front to back.