Hello all again, I have read the posts in this section but still cannot see the answer, I am going to change my oil and filter on my air cooled 2011 Bonneville, the hand book states either semi or fully synthetic oil. I always use Castrol and want the best oil in my bike, I cannot understand why Triumph can't decide which one to use, I think properly fully synthetic is the way to go but don't want clutch slip problems. What do you think then men? Ive always had good advise here. mallywoods
Truly speaking, synth or semi synth doesn't matter. What is MUCH more important for an an/oil cooled bike like yours is to change FREQUENTLY. I used to change the oil and filter on my 2010 T100 every 3000 kms or 6 months. It's cheap and easy to do and your bike will always have fresh clean oil in it. Bike specific or general engine oil? I've used both and the only difference I found was the price. Never had clutch slip issues with car engine oil. I came across some Mobil oil "specifically formulated for Triumph" bike oil at a 'flog off' supermarket so I bought half a dozen 5 ltr bottles for a 7€ a piece. Still have a bit left long after the bike has gone.
Full synthetic or blended doesn't matter , so long as it meets the specific required values required by the engine. Fully synthetic is better under higher sustained RPMs ! But doesn't last as long as semi synthetic , the mineral oil component lasts better ! Done close to 350,000 klms on triumphs over 24 year's , regular , sufficient and correct grade , with regular level checks and top up's as required , the bike will be fine !!
Just to throw my five eggs in, on the 600 Bandit Oil cooled race bike that spends it's life between 7000 & 11000 rpm we only ever use semi synthetic, but it gets changed every 2 meetings or 4 to 5 hours hard use.
To answer the original question simply and directly - they both lubricate equally well when new. The essential difference is that fully synthetic breaks down more slowly. If you do less than 10k miles per year and do an annual oil change there is no practical difference. The air cooled Bonnie uses oil to cool the hottest part of the engine round the cylinder head and valves thence via the outflow to the oil cooler and down to the sump. In hot climates fully synthetic better resists the effects of extreme temperature on the molecular structure of the oil. You pays your money......
I always use full synthetic. My bikes have run for years and years with no wear related engine issues. And use a motorcycle specific oil designed for wet clutches. Oils intended for cars use friction modifiers additives that can cause a wet clutch to slip.
Yes todays oils are all pretty good. I use semi in me 865 and fully in the 900. Always shell. Doesn't seem much different to me. Regards Joe.
The factory allows for semi-synthetic, so that is what I use. It is a bit cheaper than the full synthetic. You have to use what ever brand is available in your area. Make sure it is motorcycle rated and the proper viscosity. ...J.D.
Well thanks all for the replies and you have helped see the light and I knew you would, just one more thing, wouldn't it be nice to check the level on the centre stand on level ground, I would think that would make the correct level miles out. wouldn't it??? again many thanks for all the replies, this is a brilliant forum with lots of nice members. Mallywoods
I usually pour in the recommended amount, then run it for a few minutes. I shut it down for a few minutes to let the oil settle, make sure it is level and check the sight glass. It should be at half in the sight glass. Sometimes I have to add a bit. Depends on how well it got drained, but you don't have to get all anal. It's just an oil change. ...J.D.
