operating oil pressure

[stevey9]

I have an 82 1100L, bought it last fall and have been tinkering on it while I ride. I'm pretty new to motorcycles but not to mechanics. I noticed there was a knock which meant to me low oil pressure, so i bought an oil pressure gauge and installed it. When I first start the bike the pressure is between 9 and 10 psi at idle, after the bike warms up it will drop right down to .5 psi while idling, however when I rev it up or while riding its up betwen 6 and 8.

My question is this normal to have such low oil pressure at idle after warming up?

I'm running fresh 10-40 motorcycle oil.

[twr1776]

That is normal pressure for the two valve motors. Not sure what the knock is but have you adjusted the valves yet?

[chuck hahn]

Thats about right. Maybe a bit low at the .5 PSI, but the others look ok. Whats the idle RPMs set at? Maybe try around 1200 and see what she reads.

[chuck hahn]

The knock may be the need to do a vacuum carb syncing. And check the timing. I would check the valves and replace whatever shims are out of spec..then move on to the carb sync. Valves need done first because they effect the intake vacuum and exhaust. Then the sync.

[stevey9]

I have the idle set right at 1000 right now. I'll try raising that too 1200 tomorrow. I haven't checked the valve shims yet. how hard are they to get too and check? I'm in the process of making a carb sync tool, but i haven't found gauges I want to use yet. any chance anyone knows what the vacuum psi is?

[chuck hahn]

When you set the carb sync up its not so much the vac pressure thats important..what youre looking for is that all 4 cylinders are pulling as close to the same vacuum as possible. Go here for a full service manual and read up on the valve adjustment proceedures and the syncing...Factory manuals usually say then idle is at 1150 +/- 50...so 1200 is close enough.

http://members.dslextreme.com/users/bikecliff/

[DanTheMan]

Welcome to the forum by the way! the site Chuck referenced is done by BassCliff, our resident non-official greeter: http://members.dslextreme.com/users/bikecliff/ . It deals with all things GS and more than you ever thought you might want to know about them.

I see you're in MN, visit my profile page and you'll see there are other MN GS owners/riders around these parts.

If you haven't taken a motorcycle safety course yet, please do. I don't want to read about another motorcycle fatality. Here's the link to find one in your area: http://cfapp.southcentral.edu/motorcycle/

Again, welcome, ride safe and have fun.

My '82 1100G also makes a little noise at idle. No problems so far, it's got in the vicinity of 70,000 miles on it I think.

[stevey9]

I was finally able to get out and ride some more. I upped my idle to 1100 and now my warm idle oil pressure is at .75 but while riding its more like 3-4psi while in the 4000-6000 rpm range.

I've been thinking about putting an oil cooler on it. anyone have a link to instructions on how to do it?

[tkent02]

I was finally able to get out and ride some more. I upped my idle to 1100 and now my warm idle oil pressure is at .75 but while riding its more like 3-4psi while in the 4000-6000 rpm range.

I've been thinking about putting an oil cooler on it. anyone have a link to instructions on how to do it?

They didn't need coolers thirty years ago. Even in deserts and tropical heat.
Oil is much better now.
A cooler is a leak waiting to happen.

You can adjust the spring tension on the pressure regulator if that pressure bothers you.

[stevey9]

I'd much rather do that. I didn't it it was an option. Thanks

[tkent02]

I'd much rather do that. I didn't it it was an option. Thanks

On second thought, I don't think it will help at idle, the pressure regulator would be closed then anyway. Not even sure there is one on this model.

[bwringer]

On second thought, I don't think it will help at idle, the pressure regulator would be closed then anyway. Not even sure there is one on this model.

Right, there is not a pressure regulator on this model.

To the OP:
Quit worrying about the oil pressure. The two-valve engines don't need any oil pressure, and there's no oil pressure regulator. They use roller bearing cranks, so the oil pump just needs enough moxie to push oil up to the head. The oil passages on these engines are quite large, so there's not going to be much pressure to speak of. In other words, the oil pump just pushes oil around the engine, but there's no need for pressure lubrication anywhere.

Also, your bike does not need an oil cooler. As stated above, this just adds more opportunities for leaks to form and complicates maintenance.

Noise does not necessarily indicate a problem -- these are indeed noisy engines. However, you MUST complete a valve check and sync the carbs. And when you sync the carbs, you may find that the noise lessens or stops -- sometimes the cylinders are pulling unevenly, and this can make a noise appear at idle. And sometimes, it's just a noisy engine. Stuff in ear plugs and ride happy...


One more item -- as many others have found, making your own carb balancer is a false economy. You can easily spend $50 to $75 or more in materials and waste hours of time making an inferior instrument (and if you're planning to use vacuum gauges, it WILL be inaccurate).

Or, you can spend about $100 to order a Morgan Carbtune, a precision instrument that will last for years, won't let mercury or ATF get sucked into the engine, and, most importantly, gives precise, stable readings that make synchronizing very quick and painless. Other gauges bounce around so much that you can easily overheat your engine before getting things dialed in.

There might even be a friendly GS-er in your area that already has a synchonizer...

[1_v8_merc]

I like my cooler! There are drawbacks like the Pressure light getting stuck on, or leaks.
But I just like it for some reason....plus it looks cool.