750 oil pump gears on GS1000

[Hap Call]

Now who is this 1100ed chap? You look vaguely familiar....

[Anonymous]

So to sum up, it would seem that fitting these Star Racing gears is as valid on the 1000 as on the 1100.

My question's are:
1. Is there any possibility it could do more harm than good?
2. Would I be just as well served by fitting the stock items?
3. Is it necessary?

Thanks for everybodies input so far.

[Hap Call]

So to sum up, it would seem that fitting these Star Racing gears is as valid on the 1000 as on the 1100.

My question's are:
1. Is there any possibility it could do more harm than good?
2. Would I be just as well served by fitting the stock items?
3. Is it necessary?

Thanks for everybodies input so far.

1. There has been some debate on if this is a good upgrade. One guy believes that it spins the oil pump too fast, leading to premature failure. Another member has stated that he has seen several failures in bikes that use the gears but cannot confirm if it is the gears that are causing the problem or something else.

2. Several of the top motor builders use the 750 gears - Greg Cope and Byron Hines to name a couple. They are generally considered the best in the business and have faith in them. Like Paul said, you will have a increase in flow but due to the design of the oil system you will see little or no increase in pressure. That is not a bad thing - just the way it is. It will get more oil up to the cams where there are no roller or needle bearings supporting the cams...that is were you want it.

3. Is it necessary? If you are running stock or mild cams with stock valve springs, it is not really necessary, especially with the shim and bucket valve arrangement you have. But it sure can't hurt. I have been running them for three years with no problems in my 16 valve motor.

Hap

[cbxchris]

I went back and asked Kim Barringer at Carolina Cycle what was the deal when we saw so many sheared teeth on the overdrive pump gears in the late 80`s. His answer was that it was improper heat treatment of aftermarket gear sets. His answer was also both star and ape had a problem so as a whole all of us quit using them. He thinks possibly at that time they had a gear set that was even a higher drive ratio than what is used now. I asked his opinion of using them now...several do...he just uses external oiling kits on engines and will if asked put the gears in. To his knowledge there have been no recent failures with the current gears. Hope that clears that up a little. Also his opinion is without high seat pressure on the valves stock is fine...thats mine too. I`m not saying Kim is the best or anything just seen a lot of engines and been around a long time. He does excellent work but my grandpa moves faster 8O I`m in the process of doing a engine now...I`ll probably run the gears and pray its right. 8O

[saaz]

I don't think there is a risk of anything going wrong if the gears are decent quality. The GSX motor probbaly needs more oil due to the different valve train (adjustable rockers) exposing any oil problems to the cams etc. If you have the gears put them in...a side benefit may be more oil cooling effect from a bit more oil circulating. I do notice that when you rev the motor hotter oil comes through the oil cooler than at idle, so it is probbaly removing more heat than standard. Welcome to an oil cooled motor!

[SqDancerLynn1]

It is my understanding Using the 4V 750 oil pump gears gives a 7-8% increase in flow, Usefull when using the external top end oil lines with big cams and heavy springs

[Anonymous]

I work out that because of the different gear ratios, the upgrade on the GS1000 is around 27%! Thats a lot. Too much? Who knows.

I think on balance, with no cooler (its not hot enough over here) and with only stage 1 cams, I'm just going to stick with standard for now and rely on good oil (I've been recommended Kendall GT1 20/50) changed regularly.

I've started to become very wary of copying racers for a road bike. What works on the strip or circuit doesn't always carry over to the road.

Thanks for the help.

[cbxchris]

Yes Brit you said a mouth full there....what works on the race sucks on the street sometimes! How well I have found that out to my dismay several times....yeah and it cost a pile of money to correct it. Thats why I have a gazillion questions here already. I bought a hayabusa in early 99 when they came out and as usual I was in the engine immeadiately. I found out lots of things that do not work in that engine that are fine in a GS engine. Valve seat pressure for one. After some beat out valves and then a dropped one I figured it out. 8O 8O

[cbxchris]

I also for got to mention. All aftermarket cam manufactors USED to recommend Kendall GT-1 until the USA screwed thier oils up. If its got the star burst sign on it its not worth a sh*t...period. All the zinc and phosphorus has been removed to stop ruining catalitic converters. If I use dino oil I now use shell rotella...it is still a fleet oil and has NOT been changed. If ya don`t believe me I had a friend that did the motorcycle consumer news oil test couple years ago throw it in as a non-motorcycle oil. It bascially won the dino test. Its cheap and comes in gallons. Hopefully in GB they haven`t ruined the GT-1....I was sponsored for years by them and used to swear by that oil. 8) he he he I got another oil thread going didn`t I???? :P

[Paul]

I used to work at a petrol station years ago. Shell Rotella was a big NO NO for a petrol engine. Here in UK it was a detergent oil for diesel engines - and there wasn't many diesel cars around in those days. In other words it was designed for heavy goods vehicles.
Obviously in the States it is a different oil - I hope

[Anonymous]

I also for got to mention. All aftermarket cam manufactors USED to recommend Kendall GT-1 until the USA screwed thier oils up. If its got the star burst sign on it its not worth a sh*t...period. All the zinc and phosphorus has been removed to stop ruining catalitic converters.......Hopefully in GB they haven`t ruined the GT-1....I was sponsored for years by them and used to swear by that oil. 8) he he he I got another oil thread going didn`t I???? :P

Help!! 8O I don't know about an oil thread but you got me going!! I've got a box of 12 quarts I was planning to use. And its not cheap over here either. I've looked on the box and on the bottles and can't see a star burst symbol. Does this mean its OK? In panic I did some looking around on the net and could only find people recommending it. Oddly enough, no Kendall site to get it from the Horses mouth. I did find this though:

An "SJ" oil is not good for your Harley? because the phosphorus anti-wear additive has been reduced.

False: The marketing scare mongers that plant paranoia in the consumers mind fail to tell you that only oils 10W30 and under have reduced phosphorus anti-wear additives so this doesn?t affect any Harley? made. Any SJ oil 10W40 and above is not affected by this rule and are able to maintain whatever level phosphorus they choose. The following oils have morephosphorus content than the new Harley? 360 oil. Rev Tech, Kendall GT1, Mobil 1 synthetic, and Torco synthetic.

Can somebody clarify this situation for me? Is my expensive 20W50 ok to use?

[redliner1973]

Use it and rest easy.......the article is accurate. :twisted:

[terry]

GSX750 oil pump drive gears ARE identical to the uprated gears from Star Racing, (or Orient Express or any other aftermarket tuners)
But they are from the air-cooled 750.
I used to get them from breakers and they were from the original GSX750. Whether they uprated the gears/pump in later incarnations I don't know.
The aftermarket gears came on the market after the GSX750 - so they were obviously copied & sold as an upgrade. Bear it in mind that all they do is speed the pump up and so increase the oil flow - not oil pressure.
When Pops Yoshimura tuned the GS1000, the GSX didn't exist, so he wouldn't have had the gears available to use!
I have never heard of anybody having a problem with using these in a road engine (no matter how highly tuned)

G'Day Paul, excellent post, made more sense (to me) than some of the others too. My question though is, if the GS(X) gears increase the oil flow, how come the oil pressure isn't increased? What's the difference between oil flow, and oil pressure? How's your GSR1100S going?

[cbxchris]

Yes shell rotella is still a fleet oil here. I run it in my gasoline engine in my truck also. It is a high detergent oil for sure. But it still has high contents of phosphorous and zinc. The newer oils above 10/30 now have the star burst symbol. At first they didn`t but that has changed.

[saaz]

The starburst symbol is more to do with friction modifiers and the effect on wet clutches. The info quoted is correct. If you have any doubts, check that the oil still meets all superceded standards (SJ and lower). If it does it still meets all the older standards for wear additives etc., exactly what the bike oil people say are better!! Zinc an phosphorous levels are subject to maximum levels, they have not been eliminated. More zinc and phosphotous does not mean better protection, but longer protection, but only in cases where there is a breakdown in the oil film and metal to metal contact occurs...not really normal street conditions if you regulalry chnage the oil!!!

Most of the oil info I have seen indicates that bike specific oils have not been proven to be any better than good quality car equivalents. The more recent SL oils have higher standards of evaporation in cases of high temp conditions (sound like a good idea for bike engines!)

Most times we change the oil well before there are any potential problems, so keep on with regular oil changes. Hot running kills oil quickly. In the good old days (late 70s/80s) there was a real difference between oils, as an ordinary car oil quickly broke down, the first sign being the gear chnage not being as smooth. Using an oil like Belray was much better than car oils, typically I was able to change at 5,000km intervals rather than 2500km. The good quality car oils I use now are much better than the Belray.