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Discussion Starter #1
Hello all,

I am a new member although I have been reading posts for some time. Thanks for this resource, it is extremely helpful.

Here is the problem. I have a 1975 360T. It is running well but the transmission is about to kill me. I am having trouble with shifting past 2nd gear. When I originally tried to shift I couldn't move the shift lever at all. After gentle coaxing up and down I was gradually able to get into 1st. With some more coaxing I was able to get 2nd. I can't even get close to 3rd. This symptom was happening prior to my disassembly of the clutch. I bought new friction disks thinking they were just sticking. I have pulled the clutch cover and removed the friction disks and metal plates to replace the friction disks. While spinning the center of the clutch, I can shift into 1st but it is stiff. I can shift up into 2nd but it is also very stiff. I can't however shift into any other of the gears, 3rd through 6th are completely inaccessible. It's like pulling into a brick wall, there is no movement at all. If I drove in only these two gears I would have a Popeye calf after an hour so things aren't moving well.

The bike was running fine with no trouble with the transmission when parked 6 years ago. The crankcase had drained fully over the 6 years it was sitting (outside) due to a slow leak at the drain plug. I had refilled the bike with oil and it runs great, I am just trying to diagnose this shifting issue prior to taking any further steps forward. I haven't pulled the case cover on the left side of the bike but will if I have to. Any ideas on why this would be the case? I have heard that there could possibly be a problem with the shift forks but I have a hard time getting my head around that when the transmission was working fine before being parked. I have read that the detent spring and ball on the top of the right side of the engine should be checked but want to know if that could be the problem prior to messing with it. When I pull the clutch lever the clutch pressure plate disengages just fine, and as I said with the clutch completely removed I still can't shift easily through all the gears with the clutch and rear tire in motion. Help! I look forward to hearing your ideas.

Brooks
 

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The shift drum is the large round pipe like device with slots that the single shift fork rides on, the other 2 forks slide on the smaller pipe looking shaft.

The Drum rotates and the slots cause the forks to move back and forth.

when sitting normally, this drum and shaft sit way above the oil. Without running, all the oil eventually drips off, and the shaft and drum can rust.

CB360 Shift Drum Marked.jpg

If I had to guess, your shift drum is rusty, the other shaft may be rusty too, and the forks are binding on the drum....

You only need to remove the motor, have it upside down on a bench (After draining the oil of course) and remove the bottom case.

You will see all the gears and below them, the shift drum and shift forks. The lower pic Shows the shift forks (3 arrows) and the drum can't be seen in the pic as it is below the gears. Removing the gear shafts allow full access to the drum and forks.

Transmission and Crank Exposed Forks marked.jpg

Hope that helps, get a manual, will help more.

Also, the bearing for the transmission shafts have lock pins and lock circlips. Make sure you pay attention reassembling.
 

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Discussion Starter #3
Thanks Richard. The pictures are fantastic. I appreciate your help. I'll keep you posted when I get things opened up.
 

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It could be the shift shaft is corroded in sprocket cover?
You can check everything when motor is stripped down
 

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Discussion Starter #5
must be

It could be the shift shaft is corroded in sprocket cover?
You can check everything when motor is stripped down
I removed the engine, cracked open the bottom case and peaked inside to see...nothing! It's absolutely pristine inside, minus a bit of sludge in the bottom. The sprocket cover however was an absolute bear to get off. The shift shaft is extremely gummed up with corrosion on the outside of the case but it is beautiful on the inside. I sure created a ton of work just to polish a shaft that I could have done with the engine on the bike. I will clean up the shaft, reassemble the bike and let you know how things turn out.
 

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On the bright side, you now know what the inside looks like, you know it is good condition. Nothing wrong with that.

It is always a problem diagnosing remotely as there are many details missed when someone explains the problem.

If I was by the bike, I would of checked the shifter shaft where it passes the sprocket cover, but I thought you might of done that already. CrazyPJ was right on the money with that guess. There also can be wear on the star wheel and mechanism that change the gears. Hopefully, a clean shifter will fix you right up.
 

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Discussion Starter #7
On the bright side, you now know what the inside looks like, you know it is good condition. Nothing wrong with that.

It is always a problem diagnosing remotely as there are many details missed when someone explains the problem.

If I was by the bike, I would of checked the shifter shaft where it passes the sprocket cover, but I thought you might of done that already. CrazyPJ was right on the money with that guess. There also can be wear on the star wheel and mechanism that change the gears. Hopefully, a clean shifter will fix you right up.
Oh, I wasn't upset at your recommendation...I appreciated it very much. I was annoyed with myself for not figuring that was the problem when it took me an hour to get the sprocket cover off. I should have known it wasn't supposed to be that difficult. The star wheel looks great, the detent wheel is perfect. The drum rotates like a dream. The change arm connected to the shift spindle is my only question. There is a spring connected to that arm that rests on a pin that is screwed into the right side of the case. when I actuate the arm it taps into that pin. The travel of the arm is only about 3/16-1/2" before hitting the (stop). I assume this is correct.
 

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Yes it is. More travel and you will be missing gears
 

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Discussion Starter #9
IMAG1167.jpg After putting everything back together everything feels great. Shift pedal moves freely and returns via spring pressure. Feels very smooth. Problem is I have one bolt left over on my bench. Looks to be a 6 x 35 flange bolt but I can't figure out where it would have come from. I'm almost positive I've got all the lower case bolts back in. Possibly from inside the left engine cover somewhere? The only guess I have is the bolt that holds in the shift drum detent wheel. I don't recall removing it but I guess it's possible. Not exactly sure how the wheel would stay in place without the bolt, so that idea is a bit sketchy. There's nothing on the outside of the bike that I can think of where it would have surfaced. If you have any thoughts shoot me a line. Otherwise, thanks for the tips.
 
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