How many miles can I expect out of my low mileage RZ-350

 Simple question for you old two smoke heads: How many miles/years @
roughly 5000
miles per year can I expect out of my low mileage (bought with 5700
miles
and had the top end rebuilt shortly there after). I know the top end
goes out
at about two or three times the rate of the needle, roller and ball
bearing low end
which I figure might go as much as much as 40K miles. I'm past the
"babying
it" stage with freeway average speeds around 75-90 and the tach gets
pushed
close to redline quite a bit in the canyon. I usually get it up past
100 in
spurts on the weekend too. Also, I had a rear thumb brake installed
due to not having a right lower leg anymore (explained below). Also
new tires on this 23 year old bike.

I had new "carbon tech" carbon-fiber reed valves put in and the front
brakes bled
last week, plus a burned out tail light fixed. The brakes are way
better
now and the low end is snappier with the new reeds (more power
wheelie
prone like the old RD's now). The reeds that were in there were weird;
a
two piece Teflon material with holes on the outer set and no stops.
The guy
doing the work had to find some stock Banshee stops to use with the
carbon
fiber reeds. Also, on another ride the week before I was informed that
the
oil pump only works off the throttle so at steady speeds I make sure I
let
off the throttle and goose it at least every mile. I had three RD's
back in
the 70's and put at least 20K on them without any problems so I'm
figuring
the at least the bottom end is similar on the water cooled RZ's.

Now a bit of my history: I've been posting to alt.motorcycle sportbike
for over 6 years plus rec.motorcycles until about a year ago when it
became mostly cruiser/political oriented. I'm a one-legged, half
virtual heart deer strike survivor who's been riding two wheel-
motorized bikes since 1963. I've owned 2 air cooled RD-350's, 1 RD-400
Daytona Special back in the 70's so my latest bike is just a
lightweight extension of some of my old favorites. I've also owned
mostly Japanese 650 to liter bike's from the mid seventies to the deer
accident (GSXR1000K3 in 2004)=went out with the deer. I do some light
work (oil changes, clean & lube chain etc) but due to my current poor
health + AZ summers, I've relegated most my bike work to a trusted guy
who works mostly on old bikes and quads. My rides consist of 100-200
miles rides on Sat or Sunday mornings, mostly to and from my home in
Chandler, AZ to Canyon Lake, a twisty road East of Phoenix AZ. Myself
and others in our group usually eat breakfast at a little watering
hole called Tortilla Flat about 5 miles before the end of the paved
part of the road.

--
Bob Nixon, RZ-350, Chandler, AZ.

 

Tricky one, because you don't say which model you have. Power-valve or
early non power-valve?

The later YPVS models had stronger cranks. That said, my 1988 F2 model
ate its mains at 14k miles. I had the crank rebuilt, ran it for another
year or two, sold it with 22k miles up, and the crank let go (again) 300
miles later. OTOH, a friend has a 1987 N model, which he's had from new,
and it's done 30k and the engine as *never* been apart. Not even rings.

I think I was unlucky. I always ran it on fully synthetic oil, and ran
it in carefully. That said, I regularly used to redline it in top (which
was an indicated 127mph, IIRC). I even geared it up slightly, but that
moved the irritating 'dead zone', when the power-valve couldn't decide
whether to open or not, from 70-75mph to bang on 80, which made it a
PITA. So I put it back to stock gearing.

If it needed a top end rebuild so soon, some dork has probably broken
something.

Fundamentally, it's a remarkably strong design - one of the Brit
magazines featured some guy who'd done over 100k miles on one! The
average crankshaft life, for a power-valve model, seems to be about 40k,
but some go far longer and some (like mine) far less.

Pistons - the recommended set-up when I had mine was to use pattern
pistons, but always to use OE rings. Oh, and OE head gaskets, too.

Just ride and enjoy. If/when it goes pop, it's a stroker - it's not the
hardest thing to pull apart and fix.

Oh, if yours is a power-valve model, the endemic problem is premature
wear of the power-valve shaft in the front of the barrels, as it cops
all the road crap. This is expensive, as the barrles need re-bushing.
Apparently, a mudguard extension (fender extender, to you) increases the
life by an order of magnitude.




--
BMW K1100LT  750SS  CB400F  CD250  CB125  SL125
GAGARPHOF#30 GHPOTHUF#1 BOTAFOT#60 ANORAK#06 YTC#3
BOF#30 WUSS#5  The bells, the bells.....

 

The other problem they can suffer from is seizing up, through disuse, or
use of cheap oil, or both.

Mild sticking can be sorted by disconnecting the cables from the servo
motor, removing the PV cover on the left-hand side of the block,
grabbing the stub in a pair of pliers, and twirling it vigorously until
it frees.


--
BMW K1100LT  750SS  CB400F  CD250  CB125  SL125
GAGARPHOF#30 GHPOTHUF#1 BOTAFOT#60 ANORAK#06 YTC#3
BOF#30 WUSS#5  The bells, the bells.....

 On Aug 29, 11:15 pm, chateau.murray.takethis...@dsl.pipex.com (The
Older Gentleman) wrote:

I guess just taking off the covers and revving the engine will tell if
they're free or not. There's a black box that the cables run into.
Dunno exactly what that does. Also, on the trhrottle controlled oil
pump, is there some way the oil dribbles in at steady throttle
settings?

TIA

Bob Nixon.

 

The black box that the cables run into is the servo motor, that operates
the PV via the cables.

When the on-board computer has looked at revs and throttle opening and
made its mind up, the valve starts to open. At full chat, it's fully
open.

Fabulous device - it just *works*. Screaming top end and enough low-down
torque to be driveable around town. One of the great motorcycling
innovations.

As for the oil pump, the answer is just "yes".


--
BMW K1100LT  750SS  CB400F  CD250  CB125  SL125
GAGARPHOF#30 GHPOTHUF#1 BOTAFOT#60 ANORAK#06 YTC#3
BOF#30 WUSS#5  The bells, the bells.....