Oil Pump Gears and Half Moons

[Turtleface]

Ok, going to give the 750 pump gears a go while I have the clutch apart. I'm looking for the gears from any 16V 750, correct? I've got 82 gears lined up currently. Should I replace any of the snap-rings? Mine are in good shape, at first glance, but I'm not sure if I should treat them like malleable lock washers and cotter pins, IE, always replace with new.

I'm also going to replace my half-moons, at the ends of the valve cover. Mine seem to be originals, with 16k miles on them. They're not leaking at all, but I figured I might as well change 'em while I've got things apart up there. I've had the valve cover off many times since I purchased it, and I'm sure if I push my luck much longer, they'll eventually start leaking. I've attempted to remove the old ones previously, but stopped short for fear of damaging them beyond usefulness. They seem quite stuck. With new ones on the way, I'm thinking of just stabbing them with some sort of implement and twisting/pushing them out, carefully. Any tips on reinstalling the new ones?

I'm almost ready to bring this thing back on the road. I've replaced just every seal and gasket on the thing short of the case, cylinder, and heads, with OEM stuff to boot. Figured if I was going to with higher volume, I'd best make sure that all my gaskets and seals are up to snuff. I like to wind her all the way up to 8.5k/9k every now and then, (probably the root cause of my loose clutch hub springs) so I figure the more preventative measures I can take, the happier the motor will live. Next decision is whether to replace the brake lines with stainless, or invest in a top-end oiler. I think safety trumps motor longevity.

 

[blowerbike]

77-82 GS750 pump gears.
install the half moons backwards.

 

[Guest]

If the half moons don't leak don't change them. They are just coated metal.

 

[Turtleface]

If the half moons don't leak don't change them. They are just coated metal.

Well, new ones on the way, so I'll just keep them in a drawer until I need them.

 

[madbikebreaker]

Considering the same mod

Considering the same mod

:-kI have access to the 750 gear set in a motor that I wasn' t planning to tear into, but it seems like this is a very popular mod. Does it really make that much more volume? Is it necessary for a farily stock bike? I just hate tearing up a perfectly good motor that someone may need.
Hey Turtleface, what all did you have to remove to get to the gears?

 

[Guest]

:-kI have access to the 750 gear set in a motor that I wasn' t planning to tear into, but it seems like this is a very popular mod. Does it really make that much more volume? Is it necessary for a farily stock bike? I just hate tearing up a perfectly good motor that someone may need.
Hey Turtleface, what all did you have to remove to get to the gears?

You have to take off the clutch hub. They are right beind it. Actually the clutch turns the gear that turns the pump.
It is worth it. It flows more oil. I don't have actual numbers.

 

[Guest]

You have to take off the clutch hub. They are right beind it. Actually the clutch turns the gear that turns the pump.
It is worth it. It flows more oil. I don't have actual numbers.

30% increase is what Star was claiming, IIRC.
Tony.

 

[Suzuki_Don]

30% increase is what Star was claiming, IIRC.
Tony.

Is the extra oil flow going to blow any seals.

 

[madbikebreaker]

How does that help? Is this configuration more prone to leaks? I guess I should change my valve cover gasket if I do this. Shoot then I might as well adjust the valves. When does it end?

 

[TheCafeKid]

This is just my personal experience, but *I* have found that with the HO gears you need to run your oil level just a smidge lower, or it WILL find its way out of any weak gaskets. I used to run mine RIGHT AT the full mark, now run it about 2mm lower in the window. That and a new valve cover gasket stopped all my leaks..HEH

 

[Guest]

Is the extra oil flow going to blow any seals.

Hmmm. I can only tell you that in my case, there have been no untoward leaks or blown seals, and I have had them in for about 4 years now. A couple members have had leaks from various gaskets & fittings shortly after the mod....I'm not clear why 15 psi (roughly the oil pressure when cold) would cause a GS to leak when other bikes routinely handle 45 psi....maybe the gaskets were already compromised, and couldn't handle the additional pressure? Don't know. Bottom line, I think it's a worthwhile mod, but re. leaks, YMMV.
Tony.

 

[TheCafeKid]

Hmmm. I can only tell you that in my case, there have been no untoward leaks or blown seals, and I have had them in for about 4 years now. A couple members have had leaks from various gaskets & fittings shortly after the mod....I'm not clear why 15 psi (roughly the oil pressure when cold) would cause a GS to leak when other bikes routinely handle 45 psi....maybe the gaskets were already compromised, and couldn't handle the additional pressure? Don't know. Bottom line, I think it's a worthwhile mod, but re. leaks, YMMV.
Tony.

THAT may be true in my case as well. The only gaskets I had leak were ones I had never changed, or were due to be changed. Havent had a leak since then (only a couple hundred miles though) so maybe I spoke a bit out of turn. However, because the roller bearing GSs run a low pressure High VOLUME system, I do know over filling it will push oil out. Oil being a liquid, doesnt compress, and it needs to go somwhere.. You ever really pay attention to how much oil these things are actually filled with? I dont have the numbers right in front of me, but after an oil/filter change, its a bit over a gallon, and with a complete rebuild I seem to remember it being close to SEVEN quarts!! Ray or Terry might know better, but I remember thinking it was ALOT considering my Honda Accord only takes 4 or 5 after an oil change and its twice the size! LOL

 

[Guest]

TCK your point is noted, I wasn't taking issue, and in fact didn't see your post till after I posted....I have actually given this (oil level) some thought, when the leakage issue was being discussed (Posplayr's thread, about a month ago)...I too do not fill past the 'upper level' mark, even when I added on the 1150 cooler. Some members here put in extra oil to compensate for the cooler's volume, (some fill all the way to the top of the sight glass!) but I do not (cooler actually only holds a little more than a cup), and I wondered if that made the difference in terms of leaks....my thoughts were that the breather should vent some of the excess via windage. Again, I'm not definite as to what caused their leakage issues, it could have just been a bad gasket or banjo fitting.:-k
Tony.

 

[TeamDar]

THAT may be true in my case as well. The only gaskets I had leak were ones I had never changed, or were due to be changed. Havent had a leak since then (only a couple hundred miles though) so maybe I spoke a bit out of turn. However, because the roller bearing GSs run a low pressure High VOLUME system, I do know over filling it will push oil out. Oil being a liquid, doesnt compress, and it needs to go somwhere.. You ever really pay attention to how much oil these things are actually filled with? I dont have the numbers right in front of me, but after an oil/filter change, its a bit over a gallon, and with a complete rebuild I seem to remember it being close to SEVEN quarts!! Ray or Terry might know better, but I remember thinking it was ALOT considering my Honda Accord only takes 4 or 5 after an oil change and its twice the size! LOL

7 quarts? Even if the motor was totally apart and bone dry it still doesn't take that much oil. 4 quarts maybe 4 1/2 should be more than enough.

 

[rapidray]

Also, you shouldn't fill the crankcase past halfway up the window with the bike standing perfectly upright, NOT being on the centerstand. Ray.

 

[Nessism]

Also, you shouldn't fill the crankcase past halfway up the window with the bike standing perfectly upright, NOT being on the centerstand. Ray.

And why would this be Ray? Suzuki calls for filling the oil with the bike on the center stand, and filling to the F mark.

 

[TheCafeKid]

7 quarts? Even if the motor was totally apart and bone dry it still doesn't take that much oil. 4 quarts maybe 4 1/2 should be more than enough.

Go look at your manual bud. There are Three different volumes of oil listed in it. One with oil change, one with filter and oil change and one with rebuild. My 1100 holds over 4 quarts of oil with just a change. 3800ml. 4 quarts is 3.7something. Pretty simple math really.... If you do a full rebuild of the motor you're removing all of the oil in it. When you do an oil change, you get out maybe 4 quarts. Oil stays in all the little passages of the motor. Unless you break it down your not going to get it all out. It may not have been 7 quarts, but I remember thinking that it was a hell of alot of oil for that tiny motor after rebuilding it....

 

[blowerbike]

Dr. Dar is a bad man.
i have to agree with him josh.
also,
sometimes the right things are not in print or manuals.
check your oil holding the bike upright/unladen with the oil level in the middle give or take.

 

[TheCafeKid]

Dr. Dar is a bad man.
i have to agree with him josh.
also,
sometimes the right things are not in print or manuals.
check your oil holding the bike upright/unladen with the oil level in the middle give or take.

Oh I wasnt arguing about that.. Im simply saying it takes much more than 4 quarts to fill a rebuilt motor with oil...

 

[blowerbike]

hell i only ran 2 quarts in aspirated drag bikes.
3 QT in the turbo drag bike.
seems like 3 1/2 to 3 3/4 QT. on a street turd 1100.
maybe near a quart more for a total rebuild...
foggy foggy foggy
i dunt recall