What engine oil should I use?

[jonnycabs1861]

I have a 1997 Suzuki GS 500 with a fair few miles on the clock ( 45000Miles) what type of engine oil should i use?
It says on the bike 10/40 or should i use may be a thicker one?
Cheers John

[frankieG]

i use 40 weight

[Suzuk-E]

My 99 gs has around 37k on it. I switched to synthetic a few month ago and it seems to like it. Running a lil quieter. Doesn't get as hot. Shifting smoother.

If you DO choose to go the synthetic route...get a synthetic oil that's specifically for motorcycles.

[spc]

First: you're going to hell for bringing up this age old debate
Second: Everyone has a difference in opinion, but synthetic is overkill in the GS........and more likely to find a spot to leak from.    I used plain old castrol GTX 10w40 in my GS and dogged it out without a problem. I plan on using the same in my gixxer when it's running.  Just make sure you change it at the appropriate intervals and everything is OK

[ohgood]

How about a picture of that girl with 45k on her ?

Personally, if the dipstick is nice enough to tell me what to use, I'll be nice enough to oblige.

[sledge]

Why would you want to use a thicker oil than what the maker recommends? The GS engine has been around for decades, and it was specifically designed to run on 10/40. Use anything thicker and the pump might struggle to get it up pressure particularly with that sort of mileage on the engine and the increased wear and clearances it will now have.

I tried full synth in the GS once and didnt notice a blind bit of difference ....apart from in my wallet! I think a lot of it is down to the Placebo effect. You are convinced its going to do good and therefore imagine improvements that dont actually exsist. Synth` is without doubt superior to mineral but the question "are the benefits worthwhile in the decades old GS engine" is very debatable.

[97dime]

the only motorcycle specific oil i could find was lucas semi-synthetic 10-40.  wooks good. no problems yet. it is about $6 a quart though.

[jazerr]

Well, I don't know about you all, but a few weeks ago I made the switch to synthetic--just to see--and my gas mileage went UP by about 20%.

[spc]

If you actually have that large of a gain, there is an underlying engine problem that the synthetic is temporarily covering up

[ohgood]

Er, you're saying your mileage is typically 72 mpg with synthetic ?

60 mpg + 20% increase = 72 mpg

That, my friend is ninja 250 territory, and difficult to fathom without some fairings and heavily influenced riding technique.

IIRC some folks regularly get 70-80 mpg on those fine 250cc beasts, but it's pretty rare for a 500cc unfaired machine to keep that kind of mileage up commuting.

Not calling you a liar, just stating what I've read.

[spc]

My guess would be that his 'before' mileage was terribly low..........

[sledge]

Have you missed out a decimal? I could believe 2.0%.... but 20%?? Thats one gallon in 5 for free! Nah.

[jazerr]

If you actually have that large of a gain, there is an underlying engine problem that the synthetic is temporarily covering up

Let me actually correct myself....

I realized that I've only done freeway since I changed the oil. so it doesnt count at all. nevermind what I wrote. wasnt thinking.

[pbureau69]

question... why in 100F+ temps (ie I am in texas) not use 20w50 it would be nicer for the engine would it not?
(base-ing this question on temp guage found on bottle suggesting oil to use on engines...)

I let my dealership do the oil/filter change (yes I am lazy and I can afford it ( ) I bet I have some 10w40 oil in mine..

about syntech, I asked the dealer, and answered with a smile, syntech in the GS... its your money but won't do a thing for it, except tell you your seals are leaking.

Er, you're saying your mileage is typically 72 mpg with synthetic ?
60 mpg + 20% increase = 72 mpg

you get 60MPG on your GS.. bravo... I get average of 50-55MPG, then again I have an 05, 15K on it. (maybe the ambiant temperature makes a difference on comsumption... or the way I drive it.. )

[pnaberhaus]

First: you're going to hell for bringing up this age old debate
Second: Everyone has a difference in opinion, but synthetic is overkill in the GS........and more likely to find a spot to leak from.    I used plain old castrol GTX 10w40 in my GS and dogged it out without a problem. I plan on using the same in my gixxer when it's running.  Just make sure you change it at the appropriate intervals and everything is OK

+1

Couldn't agree more I've used Castrol in my GS since I got it in '92. I've used nothing but Castrol in my avatar pictured on the left since I got the car in 1975. The engine has no appreciable wear on it. As Spcterry has indicated, keeping the oil changed regularly is paramount to long engine life.

[mp183]

Castrol GTX 10/40 since day one.
Same in my V-Strom.
Both engines run better than new.

[yupoo]

I use mobil 1 20w-50 full synthetic. I use 20w 50 in the summer because my burns oil a little bit (quart every 1k miles if im running 10w-40 full syn . Ill probably switch back to 10w-40 in the winter. I dont care about brands just make sure it meets the ratings

[mp183]

Forgot to check the usage after my last oil change.
In the 300 miles to NJ from Adirondacks did not have any noticable usage.
On the return trip the speeds were higher so there might be some usage.
Have to check wheh I get back up there.