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Loud clunky gearchange
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Gentlemen.
My Virago XV535's down-change is, I think, louder and 'notchier' than it
should be when the engine's hot, even when I blip the throttle during the
change. Is this normal for a Virago or is something wrong, or have I got the
wrong oil in it perhaps? It's also extremely hard to find neutral when it's
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This normal, really. Engine oil should be 10/40. Gear oil in the rear
bevel box should be 85w or thereabouts.
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These will be checked later but I think it's got 15/40 in the engine and
SAE80 in the drive. It *has* got car oil in the engine though, which I
understand could cause problems. Not a super-duper car oil with extras in,
mind, just a standard mineral oil.
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If it's not fully synthetic, it should be OK, but I'd still lob 10/40 in
it, in our chilly climate.
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A motorcycle gearbox is called "constant mesh", because you have 10 or 12
gears in there that are meshed with each other and they are all spinning
whenever the engine is running. There's a whole lot of inertia involved in
all those spinning gears, and the final drive and rear wheel have to deal
with it when you upshift and downshift.
Motorcycle gearboxes don't have synchromesh like a car's transmission, they
shift gears by engaging "dogs" on the side of one gear into a slot in the
gear next to it. This process is inherently clunky, and it's aggravated by
the fact that a motorcycle gearbox doesn't have neutral between every gear,
so you can't "double clutch" the transmission and match gears, you just have
to accept the rough shifting.
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hot and it runs a *lot* faster at idle than when it's cold.
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I've had a couple of bikes (Yamaha TT600R and Suzuki TS125X)
that were very hard to find neutral on. A couple of quick oil changes
seemed to help a bit, probably flushed out the clutch fibre soup
left there by earlier owners.
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My bike was made in 1988 and before I got it last year it spent the previous
*ten* years in a dry garage. I did wonder what this might do to the innards
but the engine was fine. I changed the oil, naturally, and have changed it
since, but I think you could be right - it wouldn't hurt to change it again.
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After a couple hundred thousand miles of using car oil in relatively low
power Yamahas with excellent results I think I can say that there is
nothing wrong there! OTOH, I mostly use full synth and never pure
mineral.
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I've seen oils developed especially for big bore singles, v-twins, and
opposed twins, but I'm not convinced they're necessary. I stand to be
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You have? You mean, oils developed for each engine individually, or just
for all three?
I've *never* seen anything like that.
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Morris Lubricants do a 20W/50 which they say is a heavy duty multigrade for
single big bores, v-twins, and opposed twin engines. Apparently it has a
carefully formulated additive package. Well, it would have, wouldn't it? Who
wants one carelessly formulated?
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Well, I never. Mind you, Morris does make a lot of very unusual oils,
single grades, stuff like that. I can't see how an oil can be
specially formulated for a particular cylinder configuration, mind....
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I agree. A V-twin I can understand due to the rear cylinder getting hotter
than the front; perhaps it might need an oil better suited to the
temperature variations, but opposed twins...? Still, there it is, and Morris
seem well thought of.
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corrected though because if it's beneficial to the engine I won't skimp on a
drop of oil.
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The silver lining on the agricultural sounding Yamaha gear change is
that in my experience the gearboxes are reliable and never need
maintenance. Just be firm!
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Heh! But when I slow to a stop from 5th and haven't bothered changing down
along the way it does sound like I'm panel beating in the last few yards
*CLONK - CLONK - CLONK etc*
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Try adjusting the clutch cable.
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Seems ok but I will anyway.
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This is normal, too.
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This explains the easy-to-adjust-even-with-gloves-on knobbly screw between
the carbs then, for easy adjustment on the road.
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Oh, and yes, you hooked him, first try.
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Yes, the shifter drum will often overshoot neutral and you'll go back and
forth from 2nd to 1st because the detent mechanism doesn't stop the shifter
drum in the right place. The amount of movement
of the shifter lever between 1st > 2nd > 3rd > etc is the same for all gears,
but riders have a hard time realizing that they have to move the shift lever
further to go from 1st through neutral to 2nd so they sometimes wind up in
neutral when they don't want it.
And there is a big percentage jump between 1st gear and second gear. The RPM
increase when downshifting from 2nd to 1st is about 30%, but it's only about
15% downshifting between the rest of the gears.
Your clutch will be hotter and it won't release as well when the engine is
hot.
And, if somebody has messed around with the idle mixture screws on your carbs
and turned them too far out and compensated for the excessively rich idle
mixture by turning the throttle stop screw up, the engine won't idle down
properly when it's hot.
#39 Idle mixture screw
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Thanks for the comprehensive reply. I've stripped, cleaned, and set up the
carbs myself so they are "factory" set, though I know this doesn't allow for
wear of jets/needles etc., and balanced them, so they're as "right" as
they're going to get.
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#40 EPA anti-tamper plug (in countries that require the idle mixture screw to
be sealed, all you see is the plug.
#54 Throttle set screw
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Any thoughts? I would ask in my 'local' bike group, UKRM, but it's not as
technical as your group.
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But aren't the clowns in UKRM amusing?
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Lovely bunch of fellows, even those with red noses.
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I've only ridden a couple of 535s. Both had 'clonky' gearshifts when
compared to my GSXF, but then most bikes do when compared to a Suzuki
oil/air engine. Both were clonkier than I remember any of my Yamahas being,
but not as nasty as say an ER-5.
First off, check the clutch freeplay and set it to exactly the amount Yamaha
specify. Next, when the bike is hot, switch it off in first gear, pull the
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Do you have an XV535 repair manual? I cannot tell exactly how the clutch
release mechanism works from looking at the parts diagram, but It seems to me
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It works like any other clutch mechanism that uses a similarly placed
actuation lever.
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that there would be some slippage inherent with the worm gears as they are
initially placed under load.
Item #32: ROD,PUSH 2 appear as though the clutch push rod has TWO worm gears
on it and that the push rod *rotates* as #27: PUSH LEVER ASY is moved.
the XV250. It also shows worm gears on item #29 push rod.
Other XV models of that year used a ball and ramp clutch release mechanism.
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clutch in and check for excessive drag. It will drag a bit, but if you can
get the bike onto a milk crate ( just get the rear wheel clear of the
deck ), you should be able to turn the rear wheel with the bike in gear,
with the clutch in, by hand.
If you can't, the clutch isn't fully disengaging. If you can, then all is
well. There are many possibles and some probable causes there.
If the clutch isn't fully disengaging, it can make neutral finding a bit of
a pig. Some bike are just a pig sometimes anyways. Call it character.
As for the oil, semi-synth or mineral that meets JASO is all the engine
needs.
I quite liked the 535. Went OK, was fairly comfy, went round corners in a
not unamusing way and had brakes that worked. A nice little bike really.
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Exactly me feeling. Lovely soft torquey engine, too. And shaft drive,
which is unusual in such a small bike.
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