Messages

Thanks for the tip.
Strange thing is there is no such wire on the original harness, so that would mean the gauge lighting originally is coming from a different route?

Thank you.

Just checked. Yes, the blue wire ending in a double terminal connector has a black line tracer on it.
I'm thinking that means the loan solid blue wire should be connected with the blue wire running from the original 4 plug connector running back into the bike, and the blue wire with the black tracer line and double-ended terminal should be connected to a blue wire and a black wire found in the headlight that had originally communicated with the blue wire going into the original 4 plug connector?

I have a question about the wiring of the right switch assembly.
I ended up with a new "4 into 1" replacement to instal.

All the wires are colour coded which is great, however instead of a 4 wire clip attachment, there are 5 wires, 2 of which are in a 2 wire clip.

I'll have no trouble connecting the 4 colour coded wires, however instead of one blue wire, the new assembly has 2 blue wires, one of which ends in a double head to attach 2 wires.
So basically there now 3 blue terminal connections instead of just the one that went into the old clip.


I'm wondering which of the 2 blue wires to connect to the blue going through the bike from the old clip, and then what to do with the other blue wire terminal connections on the new assembly?

I think the issue is my RD is an E model.
"4 Into 1" noted on the item description that E models my require a minor wiring adjustment rather than just plug and play.

Thanks for any advice you can offer.👍

Yes,
This bike was originally silver.
Hemi

Yes,
My original '77 back in the day was a D model.
In Canada, the E's arrived the tail end of '77.
Hemi

Spent the winter restoring a 1977 RD400E.
Still some carb work to do, but otherwise ready to roll.
Brings back sweet memories from my late teens when I bought my first new bike, a 1977 RD400D.
Hemi

Jspooner,
You nailed it!
Disassembled the forks today, and found the top out valve had been reassembled incorrectly by the previous owner.
The oil flow ring that contains the spring was upside down, easy to see how that could happen.
No more clunk at extension, hard to believe that little spring and ring make such a big difference.
Many thanks!
Hemi

Jspooner,
Appreciate your advice. Seems you've experienced the very same issue and found a fix.
Fingers crossed that's the issue.
Sounds like it took you a few attempts to get the parts inserted correctly.
Hemi

Thanks Dvsrd,
I've tried more fork oil, thicker oil, less oil.
With more oil, the forks seemed a bit more extended at rest, felt stiffer, less sag, still had the clunk.
I'll check the other things you mentioned.
Hemi

Jspooner,
I've checked several parts diagrams and I don't see the springs you noted at the bottom of the forks?
I can't seem to paste a photo here.
Hemi

Thanks Jspooner!
That gives me something to work with.
Found a couple parts diagrams.
Looks like there are several parts that come together in the  bottom of the forks.
Perhaps the previous owner re-installed incorrectly.
Hemi

STLMike,
That's very interesting.
Let me know how that works out for you when you ride your bike after reassembly.
I've been talking to John at Economy Cycle. He sold me the progressive springs.
He has 2 personal RD400's, one with progressives and the other with stiffer springs for the track.
He hasn't mentioned cutting the springs, and I believe the spacer is supposed to be removed with progressives, leaving about an inch of spring above the tube with forks extended prior to replacing the caps.
Before I switched to progressives, the forks had the spacers and stock springs, and had the same problem, a nasty clunk at full extension.
Hemi

Ok,
Thanks Jspooner,
Looks like it time to disassemble the forks.
Hemi

Also,
The fork tubes were supplied by HVC Cycle- part number 1A0-23124-00-00, 1A1-23124-00-00
Hemi

Thanks Jspooner,
Yes, the previous owner installed the new fork tubes.
Perhaps the damping rod was reassembled incorrectly?
Any other ideas out there would be appreciated.
There are no spacers with the progressive springs.
Either way, with progressives or the stock springs and spacers, there is about a 1" extrusion out the top of the forks before screwing the fork cap back on, which I believe is about the correct amount.
Hemi