Author Topic: Transmission??  (Read 802 times)

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Offline Pinhead

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  • 1979 CB652-ST
Transmission??
« on: August 12, 2010, 04:55:36 PM »
I've got a '79 CM400T that I've been driving around everywhere until recently. The bike sat on my back porch for about a week while I was running errands with my pickup. When I jumped back onto the CM, something was amiss; it wouldn't shift into 2nd, 4th, or 5th. When it feels like it should be in these gears, the bike just freewheels. 1st and 3rd work perfectly. This was strange since the bike ran and shifted perfectly when I parked it. I drove it around the block a couple of times today trying to see if it was the linkage or the internals of the tranny. ONE time i got it to shift into 4th gear (and drove), but once I shifted back down at the stop sign all I had was 1st and 3rd again.

The shift linkage "feels" like it's going into all of the gears.

With the bike sitting still on the centerstand and engine OFF, I can sometimes get it to engage into all 5 gears. Never twice in a row, though.

What the heck is going on??
Doug

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Offline mystic_1

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Re: Transmission??
« Reply #1 on: August 12, 2010, 10:08:13 PM »
Could be a broken shift fork.  Not familiar with the CM400T gearbox internals, but here's the chart of the gear actions on a 750, as you can see if one shift fork is borked that can affect more than one gear.

mystic_1
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Offline Pinhead

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  • 1979 CB652-ST
Re: Transmission??
« Reply #2 on: August 29, 2010, 12:51:35 PM »
After being scared for months to tear into the transmission I finally convinced myself to work on it. I wish I would've done this sooner, as the fix was SO simple anyone could've done it!!

All I had to do is remove the clutch basket and tighten one bolt. ONE BOLT!!

It was bolt number 14 in this picture.
Doug

Click --> Cheap Regulator/Rectifier for any of Honda's 3-phase charging systems (all SOHC4's).

GM HEI Ignition Conversion

Quote from: TwoTired
By the way, I'm going for the tinfoil pants...so they can't read my private thoughts.
:D