Author Topic: '77 Rd400 not shifting into 1st. Acts like its in neutral all the time  (Read 368 times)

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Offline Cocoablini

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Hi, I replaced the clutch cable with one from EconomyCycle (specified length for rd400).
Seems fine-maybe a little less stiff than older one.
Now bike won't engage 1st when idling.
Symptoms are when not running:
-Neutral indicator works and goes on and off
-I can mostly shift down from N to 1(when bike is not running) and up to 2.
-Sometimes I cannot get it to accept 1st but if I roll the rear wheel on center stand that allows me to shift clutchless or clutch in
-When I shift down to 1st, there is the requisite "clunk" and neutral light goes off BUT if I roll the rear wheel it moves freely for about 5 degrees before I hit resistance.
-I can rotate the rear wheel when in first gear with heavy resistance
-Clutch wormdrive operates and the cable appears to be correctly installed and actuating the wormdrive which pushes the pushrod . I did grease that a bit and the ball bearing came out so I put that back in and the pushrod.

Am I somehow in a wrong gear? Any tricks? I didn't do anything else except new cable and cleaned the clutch actuator (wormdrive and pivot). The shifter DID make a big noise once but it skipped the spline and moved. Not sure what I could have done.
I will try and send a pic of the cable installation. Maybe I bunged that up but it seems pretty straight forward to me!

Offline AndyDean42

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Re: '77 Rd400 not shifting into 1st. Acts like its in neutral all the time
« Reply #1 on: September 09, 2022, 08:32:14 PM »
I would try readjusting the cable, if you can rotate your rear wheel without clutch lever pulled in then the clutch is partially disengaged. Sometimes new cables stretch a little on initial operation. Also worn shift lever splines are quite common both on the shaft and the lever. You can replace the shaft but requires the clutch cover removing to do it. They are readily available in the US from HVC or EconomyCycles.

Andy
RD400C, RD350B (new project), GS750E

Offline Cocoablini

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Re: '77 Rd400 not shifting into 1st. Acts like its in neutral all the time
« Reply #2 on: September 09, 2022, 11:45:01 PM »
OK, I shall try that. I did get this nifty clutch cable adjuster since the old one was trashed. Easy to use and do micro adjustments

Offline Cocoablini

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Re: '77 Rd400 not shifting into 1st. Acts like its in neutral all the time
« Reply #3 on: September 15, 2022, 11:51:12 PM »
I am thinking the wormdrive isn't going in far enough. Since I have a new cable, I tried adjusting at handlebars but engine still revving and not getting into gear when I shift.
Shifter seems good as I get a good thunk when I click it to first and second and neutral.
My question is, maybe cable is too slack and there is the engine side adjuster with the nut and philips head screw on the inside. Clymers says loosen the lock nut to allow slack and adjust screw.
Does this twist the wormdrive into the clutch rod/ball bearing deeper(tightening?) See attached

Offline Astute Greaser

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Re: '77 Rd400 not shifting into 1st. Acts like its in neutral all the time
« Reply #4 on: September 16, 2022, 12:24:23 AM »
Yes, it does adjust position of worm. Slacken locknut. Wind in screw till resistance met. Slacken off 1/8 of a turn and lock off.
I recently had problem at the other end of the change shift. There is a ratchet type mechanism where in your case 2 change levers, push/pull the dowel pins (hamster wheel) at the end of the shift cam. The lever positions are controlled by an adjusting screw (cam) that fits between the two legs of a spring. This is locked in place by a nut and washer. If it’s slackened off, you get change problems. Easy to fix but you have to take off the clutch. Look up the manual how to adjust and in which gear it should be done.
But as problem has occurred at cable change stick to that first. Refit the old and see if problem still there.
« Last Edit: September 16, 2022, 09:35:40 AM by Astute Greaser »

Offline pidjones

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Re: '77 Rd400 not shifting into 1st. Acts like its in neutral all the time
« Reply #5 on: September 16, 2022, 01:23:44 AM »
Really sounds like a) you need to adjust your clutch by the FACTORY Yamaha manual and b) you need to burn the Clymer manual. The '76 RD400c manual can be downloaded here https://www.aircooledrdclub.com/manuals.html I believe it applies to the D model also.
"Love 'em all... Let GOD sort 'em out!"

Offline Cocoablini

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Re: '77 Rd400 not shifting into 1st. Acts like its in neutral all the time
« Reply #6 on: September 17, 2022, 02:23:05 AM »
OK, as per  @pidjones recommendations,
-Threw out Clymers(trash)
-I reset the handlebar clutch adjuster all the way in.
-Loosened engine side clutch locknut
-Turned screw and backed off an 1/8 or so(like factory standard)
-Started up bike and still wouldn't move but it kind of tried(improvement!)
-Started turning out handlebar screws(tightening) and got more movement
-fiddled with engine side setting and handlebar adjuster in relationship to each other.
-BINGO!

Seems like engine side needs to have a lot of play for maximum movement for the wormdrive
Whereas the clutch handlebar lever needs to be tighter so the cable is most responsive.

On another note that may be of interest, I never touched this engine-side adjuster since I got the bike and with the lower and upper adjusters sort of sync'ed for best performance the throttle response has been so much better. I am wondering if the old cable(and new) just didn't get the plates engaged correctly. When the clutch pull arm can be actuated with the best leverage(handlebar) and distance(worm drive) the shifting and engine surging/gugging has stopped.. So I am guessing it was partially engaged the whole damn time? I was tearing up the neighborhood shifting nicely and no throttle weirdness which I assumed was a carb issue

Thanks so much again! Rebuild adventures continue