Steering Dampening on the XJ-RK

After roller bearing installation, should I reinstall it? .. My other XJ is not equipped. Does it need any servicing ? How does it work? (round disc mounted on the bottom end of the steering tube)
Thanks
Al

 

Wow.

You're in some interesting company there, I wonder why Yamaha felt the need to fit it to the revised 750 Seca. According to the Haynes, the factory fairing-equipped bikes got a piston-type damper.

I looked in the fiche. PN 5G2-23490-00-00 (214-23490-00-00) DAMPER, SHIMMY ASSY. It's an "assembly" all right, and it cross-references to a LOT of "very interesting compared to a 750 Seca" bikes:

1970 RT1
1970 RT1M
1971 DT1E
1971 DT1MX
1971 RT1B
1971 RT1MX
1972 DT2
1972 RT2
1972 AT3_CT3 (AT2)
1972 AT3_CT3 (CT2)
1973 DT3
1973 RD250
1973 RD350
1973 RT3
1973 TX750
1973 AT3_CT3 (AT3)
1973 AT3_CT3 (CT3)
1974 RD250A
1974 RD350A
1974 TX750A
1975 RD250B
1975 RD350B
1983 XJ750RK

As far as serviceability, does it look like it comes apart? From the crappy artwork in the fiche, it looks like it might be riveted together. I found one from an RD on eBay, and that one looks like it's screwed together. Can you post a couple of pics of it (both sides?)

I would say if it comes apart, take it apart; clean and lube. Take pics.

If not... I'd hate to say, flush it out with brake cleaner if its innards need lubrication, there'd be no way to re-lube effectively. If it can't be easily disassembled, I wouldn't mess with it too much.

I'm sure it works like any other rotary steering damper; it gently impedes handlebar motion, to prevent "shimmy." Old Triumphs had an adjustable one consisting primarily of a leather disc between two big washers.

As far as needing it, I really can't answer. It certainly wasn't shown on the '81 750R, no idea why Yamaha suddenly decided it was necessary. Unless Haynes is wrong, and it was fitted because of the factory fairing packages; or the sudden popularity (at the time) of aftermarket fairings.

I know where you can get a brand new, NOS one for a paltry $128.16. 8O

Fascinating.

 

Thanks so much for your response ... it is screwed together, I reinstalled it, sprayed a little WD-40 on the spline. when installed it does seem to slightly toughen the motion with the roller bearings. It's an easy take-off, so I'll try it out for a while and see how it goes.
I agree, strange Yamaha would install then cancel