40 year old motorcycle shop recommends Conventional 10-40 Castrol only

cbrf3

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Yeah, somebody stuck those (not so good) K&N's on mine too when I got it. They were the first things to go for my restoration. Have a newish set of 4 if you want them.
Mine came with Uni Foam pods filters but over the years the foam deteriorated and only the springs and end caps remained. The Dynojet stage 3 kit paperwork mentions to use K&N filters with a 4 into 1 pipe. I was going to give them a go but the price for them was just too steep!
 
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For the OP (cbrf3), here's my daily rider on Richard Russel Parkway from this summer. It's amazing how far things have come.
ZX14R Richard Russell 2022.jpg
 

cbrf3

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Yes, technology has marched on. The GPz has been in the corner of my garage for almost 25 years. I started to look at motorcycles again and was not ready for the prices or having traction control and antilock brakes. Thought it would be easy to get this 40 year old bike back running to retest the waters on the street. I am not exactly a mechanic, but my son and I are trying to get it working correctly but there is always something setting us back. Brakes/lines have been either replaced or completely rebuild, all electrical connections have been checked & sprayed with DeoxIT and have totally gone through the carbs.

Had it running for about 5 minutes with a lot of smoke but had to shut it down due to a leaking petcock and an idle that would not settle down below 2500 rpm's. Have a kit coming for the petcock but not sure why the idle climbed as I finally was totally off the choke. I hope I can get it reliable enough to at least take it around the block soon... :rolleyes:
 
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As Zee had pointed out you can get the Valvoline conventional oil for a good price from Walmart, they should also have their full synthetic version for not really that much more. Castrol also has a blend that you could try called Actevo 4t, mainly just go with a motorcycle oil that has Jaso MA or MA2 listed, I think MA is the more universal one and MA2 is for newer bikes that have a catalytic converter but other than that their mostly the same.

I used the Kawasaki conventional oil when breaking in my Ninja 650 but then switched to the Actevo, used that for a couple of changes and then switched to the Valvoline full synthetic.

If you try an oil that doesn't for whatever reason work for you don't be afraid to dump it early and switch to something else, every bike is different and what works for someone else may not for your bike. If you find yourself trying out different oils I'd just reuse the filter as most likely you won't have that many miles on it anyways.
 
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Was happy using 20W-50 regular motor oil for that era of bike back in the 70s/80s. Current 2013 Triumph Thruxton seems very happy with Mobil 1 15W-50. Never experienced clutch slipping issues in any of the bikes (Honda, Yamaha, Triumph) and said M1 is good value and widely available in 5-quart containers. Needless to say, I do all of my oil changes and servicing myself whenever possible.
 

ZeeOSix

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You guys realize JASO came about around the year 2000 do you?
There is absolutely no need for JASO in this thing. Same with synthetics, on such an old thing, I would not do it.
There was a reason JASO formed in that time period. Oil formulations have changed over the years, and using a JASO rated oil would be more like using the oils that were around pre-2000 than the oils that are non-JASO today.
 
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".....JASO rated oil would be more like using the oils that were around pre-2000 than the oils that are non-JASO today."

Interesting to read this as others have commented that JASO spec'd oil is critical for wet clutches, assuming correct weight is selected. For info. M1 15W-50 is NOT JASO rated.
 
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I've used Castrol Actevo 10w40 blend with very good experience on my 1981 Suzuki GS650G. Not even an oil cooler. It seems to do fine on as much as 4k mi. OCI. One of the many one model oddities on that bike is that it also uses the sump oil as a primary lube rather than a separate gear oil supply. That may add some oil workout. The only other oil I used in this bike was a one time with Rotella 15w40 T6 syn. Shifting seemed to get strange after 1500 miles. All three of the shaft drive GS650G models have a plain bearing, high oil pressure engines. Suzuki's first choice was 10w40, OK'd 20w50. I've only avoided the 20w50 to save strain on the oil pump on 40+ yr. old bike. I may be wrong about that.

I changed out clutch springs at one point due to a bit of strange engagement feel. Used OEM springs, not HD. That was an improvement even though the new springs were only about 1/10 in. longer than the originals.
 

cbrf3

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I suppose I will keep the M1 4T as I was planning to run the old Honda GN4 oil about 1300 miles to get the odometer to 16,000 then do 3k changes with full synthetic. For me that might be the riding season per year. Wanting to do one-year changes as the whole exhaust has to be removed each time. 1982 manual recommends 3100-mile oil changes. Seems like a stretch with that era motor oil, might be a bit much with today's conventional in this motor/gearbox. Notchy shifting and it will have to be dumped as well.

Thank you for the encouragement from everyone. It is a time/skill and money thing trying to work out the issues.
 
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I have had a 1982 Honda 450 Nighthawk for the past 30 years. I am the second owner. I have only used Rotella 15W40 as did the original owner. Everything is original on the bike except for wear items.
 

ZeeOSix

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Wanting to do one-year changes as the whole exhaust has to be removed each time.
After market exhaust? Never heard of or seen a factory exhaust every having to be removed to change the oil.
 
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Sometimes the exhaust have to be removed when you want to change the oil filter. These old Kawasakis have a catridge oil filter at the bottom of the engine.
 

cbrf3

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I believe the pipe is tucked under the bike for ground clearance. A lot of these bikes were raced.
I cannot even access the drain plug. :rolleyes: I thought about sucking the oil out from the fill but that is a no go.
 
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