HP4 or GN4?

Joined
May 17, 2001
Messages
573
Likes
0
#1
The guy I bought my 98 XR400 from used HP4. At my local shop, it runs $7 a quart. What is the difference between HP4 and GN4? I did a search, but couldn't find any info already posted except someone saying use GN4, HP4's too expensive. Is the HP4 that good? I'm not trying to be cheap, but I don't want to waste my money buying it if there's no need to.

Thanks,
Jeremy
 
Joined
Aug 5, 2001
Messages
309
Likes
0
#2
Hello,
I used to use Castrol automotive, never had problems. Then one day I picked up GN4 for ~$3/qt. and tried it. Shifting is very noticably smoother. I've never used anything else since. HP4 is just a sythetic version of GN4. I believe that whatever oil you use, if you change it very often, it's better than just using "better" oil. Besides with the $ you save, you can almost buy an oil filter and change it every time you change the oil, rather than every other time like I've heard. I say go with the GN4 and change it and the filter every 100 miles or less, depending on how hard you ride. Good luck, and keep on thumpin!
 
Joined
May 17, 2001
Messages
573
Likes
0
#3
ok, I drained the oil, and put in a new filter, and cleaned the strainer screen. I'm going to go with GN4. Is it ok to mix the HP4 and GN4? I have about 1/4 of a bottle of HP4 left. Can I put that in, then GN4 for the rest?

Jeremy
 
Joined
Apr 21, 2000
Messages
55
Likes
0
#4
As slick as you wanna be...

GN4 is a very good petroleum based oil. HP4 is a VERY good semi-synthetic oil. If you run your bike very hard, like desert races (sustained high speeds/high RPM), or woods racing (no air flow through motor), you might want to use the HP4. I used to run it in my street/roadrace bikes, with no failures.
You can mix oils (motor oils, that is...).