Triumph Rat Motorcycle Forums banner

Synthetic vs mineral oil in t140v engine

15K views 117 replies 26 participants last post by  tridentt150v 
#1 ·
I'm working on a 1973 Bonneville t140v that hasn't been started for 3 years for a friend. I have changed the oil, removed and cleaned the frame filter and sump drain filter. replaced old oil with Redline 20wt50 4T full synthetic. I've heard some opinions that mineral oil is better for the older engines. I use full synthetic in just about everything I own. Does anybody know a good reason why I shouldn't run full synthetic in this bike? Same oil I use in my 2006 Bonneville t100. Thanks Dan B.
 
#2 ·
That grade would seem ideal being a 20/50. I am happier using a mineral 20/50 designed for air cooled engines and change it at 1000 miles. There must be dozens of different choices out there and all will do the job of keeping metal surfaces apart. More important to keep an eye on routine changing of whatever you put in.
I get very low wear rates with modern oils of any make i use..
 
#3 ·
Hi Dan, That is an outstanding good oil. I personally use Mobil1 v-twin 20-50. Both these are very good. For sure have excellent hot & cold weather characteristics. John has pressure gauge on his '69 Bonnie. Uses Mobil1 v-twin. The cold oil pressure is not too high & the hot oil pressure at idle is not too low. Better pressure smoking hot than even straight 40w.

Motor wear in general is reduced especially in very hot weather like we've been having lately. I have found cam wear is very good now also. Some say it will make old motors leak, but my experiments show it leaks the same. Only good things happen with these oils. The only down side is cost. However overall I feel it's way cheaper than motor overhaul. Have seen it used in several old bikes from storage without problems & doesn't cause more oil consumption.

Red Line V-twin transmission oil didn't work out too good for me & a few others. It's like too slippery. The gears take longer to coast to a stop in neutral pulling in clutch & in clunks way worse during shifting. Odd as it's sold for Harleys to reduce clunk. It puts an odd pink foam inside trans that takes several oil changes to get out. I use StayLube from Monument Car parts. States good for non ferrous bushing on bottle.

You are in Concord CA! I'm just next door in Pleasant Hill. I'm very busy for the next 2 weeks. But after let's meet for a ride.

You may have seen me around town. Blue/white '73 Tiger 750 all stock. I ride at least a few times a week. A few of us in Diablo Valley. John's in Oakland. We meet & ride Canyon, Pinehurst, Redwood Rds. to Castro Valley. That's our coffee run. Often we extend it for 100 miles.
Don
 
#79 ·
Hi Dan, That is an outstanding good oil. I personally use Mobil1 v-twin 20-50. Both these are very good. For sure have excellent hot & cold weather characteristics. John has pressure gauge on his '69 Bonnie. Uses Mobil1 v-twin. The cold oil pressure is not too high & the hot oil pressure at idle is not too low. Better pressure smoking hot than even straight 40w.

Motor wear in general is reduced especially in very hot weather like we've been having lately. I have found cam wear is very good now also. Some say it will make old motors leak, but my experiments show it leaks the same. Only good things happen with these oils. The only down side is cost. However overall I feel it's way cheaper than motor overhaul. Have seen it used in several old bikes from storage without problems & doesn't cause more oil consumption.

Red Line V-twin transmission oil didn't work out too good for me & a few others. It's like too slippery. The gears take longer to coast to a stop in neutral pulling in clutch & in clunks way worse during shifting. Odd as it's sold for Harleys to reduce clunk. It puts an odd pink foam inside trans that takes several oil changes to get out. I use StayLube from Monument Car parts. States good for non ferrous bushing on bottle.

You are in Concord CA! I'm just next door in Pleasant Hill. I'm very busy for the next 2 weeks. But after let's meet for a ride.

You may have seen me around town. Blue/white '73 Tiger 750 all stock. I ride at least a few times a week. A few of us in Diablo Valley. John's in Oakland. We meet & ride Canyon, Pinehurst, Redwood Rds. to Castro Valley. That's our coffee run. Often we extend it for 100 miles.
Don
Same here. I always felt it was the best oil for several reasons in my experience, not thru listening to what others say. But maybe the most telling experience is that my Thunderbird 1700 has the infamous knocking issue many have, and mobil 1 V twin is the ONLY oil of many i have tried that actually made it dead quiet. And i have tried many from rotella to motoul, castol, you name it. After about 1000 miles I started to get a little noise again and now at 2000 it's still there but just a tiny bit and not near as often. No other oil has even quieted it down at all except torco which worked maybe 1/2 as good as M1 V twin at best. The kicker was when i read a member's post elsewhere that started he worked for a oil co that was trying to develop an oil to compete with M1 and gave up after finding they couldn't come close ! They said they found M1 lasted twice as long as any other oil they tested or that they came up with. Thats 3rd hand info but if true it speaks to why it has been the only oil that could quiet my engine to such a great degree. I'll never again use anything else.
 
#6 · (Edited)
I use a semi synthetic in the Trident seems fine, people say about using mineral in old engines because its designed for air cooled, but you have to remember that a synthetic is designed to take much higher temps than mineral so thats why i use it for air cooled as it will hold up better at higher temps.
 
#11 ·
Hi Dberto,
Any motorcycle specific oil made after the 1990’s will be far superior to anything produced while these bikes were in production, viscosity range is the key, especially the upper number- */50 or 60. The brand usually depends on local availability and personal preference.

If I was going to run a new sports bike with OHC, Fuel injection at 15,000 RPM, I would use a well branded good quality Fully Synthetic oil that is readily available.
On my 40 year old Triumph I use a well branded good quality Fully Synthetic Oil that is readily available.

After all, metal sliding on metal is metal sliding on metal, however old.

The AMA found vehicles using Fully Synthetic oil performed 47% better in standard tests.

My preference is Mobil 1, mainly due to reputation and availability.
The high Zinc Penrites looks interesting, but it is a special delivery item where I live.

Redline oils have a great reputation for quality.

Regards
Peg.
 
#14 ·
I myself prefer Amzoil full synthetic 10-40 oil and Amzoil filters myself. I've been using their 0-30 in 2005 Sion XB after my first twenty thousand miles on it, and now I have over 210,000 miles on it and it still runs like a brand new car. I use Amzoil full synthetic 10-40 along with there oil filters too, on my Boober and I'm very happy with their oil. Plus, they ship it right you and that usually takes about three days to receive it. But everybody uses what they like and if there is another oil out there that you'd prefer to use, then go for it. But if I were you, I'd use a full synthetic oil on your bike that meet your manufactures specs. So you don't void your warranty. But there are a lot of great synthetic oils out there, just use the oil that you like the best and stay with that brand. Same with oil filters also. K & N makes a great synthetic oil filters and so does Mobile One too. They make a very good synthetic oil and filters also. This is a very good site for info like that and even more good info, about other Triumph related stuff. Good luck and I hope this helps.
 
#18 ·
I cant think of any reason not to use full synth moto oil in a 70s Triumph ..science is science ,it lubricates better , that's all . And when it comes to old british bikes..they don't make them like that anymore ,all the more reason to make them last as long as possible . I have a 77 and use Mobil1 20/50 . I would recommend adding a filter in the return line no matter what oil you use .
 
#26 ·
If your clutch slips when you use Mobil 1, drain it out and soak your clutch plates overnight (I use diesel) and use motor oil intended for wet clutches.
Mobil1 motorcycle oil is intended for wet clutches (says so right on the bottle ) and doesn't have the friction modifiers the automobile oil does . Ive been using it almost 10 year in my bonnie , no clutch slip .
 
  • Like
Reactions: Doc Snakesfield
#21 ·
Don't use car Mobil1 with wet clutches it will slip. Only use the V-twin Mobil1 for motor cycles. Specifically formulated for wet clutches. Frees well, yet no slip.

Generally speaking if you put car oil in primary breather bikes or primary case the clutch will start to slip in about 10-50 miles.

If you drain frame or tank, motor sump, primary & install wet clutch compatible oil ride the bike gently to prevent clutch slip. After about 20-100 miles it often will cure it. Sometimes you have to change the oil more than once. I've seen this on several bikes now including my own. Saves taking the clutch apart. Worth a shot.
Don
 
#60 ·
Don't use car Mobil1 with wet clutches it will slip. Only use the V-twin Mobil1 for motor cycles. Specifically formulated for wet clutches. Frees well, yet no slip.


Don
Late to this party and sticking my nose in again I know.

Strickly speaking the Trumpy clutch is not a wet clutch, the piddling bit of oil in the PC splash feeds the chain if kept topped up. But of course this no news to owners.

The clutch plates do gather some oil but never enough to worry them into slipping. Clutch slip may be about an endless number of issues none of which include oil. IMHO of course. :laugh2: RR
 
#25 ·
If you shop at Walmart's, Quicksilver 20/50 full synthetic motorcycle oil is 4 bucks a quart cheaper than Mobil 1 Vtwin oil..It's distributed by Mercury Marine and a lot of Japanese bike riders like it..
 
#27 ·
Full synthetic is not necessary for the Meridens as you have a sludge trap and if not cleaned may well result it the sludge moving through the motor. The screens are not really filters. The oil must be changed every 2000 miles or sooner. Synthetic would be a waste. If your motor has had a rebuild and the sludge trap was seen to then synthetic could be used but should still be changed every 3-4000 miles. Dino or synthetic oils have the same protective factors up to a certain mileage, dino perhaps at best 5000 miles, full synthetic could be double but who risks that.
 
#29 ·
Surprised no one has mentioned the two issues with modern synthetic oils that I was taught years ago by wise men of the classic Triumph world. I do use full synthetic Amsoil (I'm even a dealer) in all but my old Trumpies. I've been using full synthetics in all my engines since 1977 for all the reasons that have been mentioned.

The negatives for old bikes are:

1. The cam lobes and pushrods of these old bikes are not hardened like newer ones, and definitely need ZDDP to minimize wear on them - the old days all oils had high levels of ZDDP for this very purpose. But years ago it was generally outlawed for most oils - but you can find some oils blended for old vehicles that do have it in good quantities. Or you might even find it as an additive.

2. I have always heard that modern synthetics have an acid in them that will slowly degrade brass/bronze parts - parts with copper in them - causing pitting and some loss of material - and that such parts are indeed in our old Triumph engines.

For a number of years I have compromised with a 20W/50 product made by Brad Penn oils. It does contain the high level of ZDDP needed for the cams & pushrods, and is partially synthetic, reducing the negative effect that might occur to the brass/bronze parts that might be more seriously affected by a full synthetic.

Seems to be the perfect oil for all my old Triumph's..........

HTH,

GN
 
  • Like
Reactions: Doc Snakesfield
#31 ·
Those wise men may have been wise but not well informed...A lot of people use full synthetic oils in old British bikes for many years with no issues you mentioned.Mobil1 Vtwin oil being one is popular..And you might be surprised that not all oil made years ago had high ZDDP levels...Triumphs had known exhaust cam wear problems which led to the exhaust cam tappet oil feed and finally nitrided cams...
Brad Penn is a very good oil ...There is some discussions on car forums about it still being good because of a change in company owners...
 
#30 · (Edited)
#32 ·
Don't doubt it may be a tale - but with my old Trumpie's I'd rather be safe than sorry.........and they say the partially synthetic retains most of the great properties of full.......but then, maybe that's an old wive's tale too.......... ;-)

GN
 
#33 ·
That's all that I ever use in my engines also, is Amzoil. I'm an Amzoil preferred customer. So, I get a big discount on my Amzoil products, by buying directly from Amzoil. For instance, I only pay 35.00 for a gallon of of Amzoil Metric 10-40 oil. But, if I wasn't a preferred customer, I'd be paying about 30.00 bucks more for the same oil from Amzoil. I think I pay around 8.00 bucks for there filers too. I've tried Redline, Royal Purple, Lucas, and Mobile One and they're all good motor oils. I just prefer Amzoil products myself.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top