I meant to post this many months ago. I have a 2016 Bonneville T100 with only 2300 miles on it. Unfortunately, I noticed right out of the box that the shifting is noisy and rough. Mechanically, it sounds/behaves like there’s insufficient lube in it, or that the viscosity is way too light. I don’t think either of these things are present (I use 20W50) but … I had hoped that, in time (with many more miles rode) the gear box and shifting would become much smoother & quieter but such has not happened. Has anyone else noticed this on the Bonneville T100?
I would agree that the shifts are 'clunkier' and not always as positive as I would like but nothing I can't live with...definitely helps if you match revs by blipping the throttle.
The oil you are using is not too light, it is too thick. The specified grade of oil is 10/40. Are you using a car oil? They have additives which are not compatible with motorcycle wet clutches and cause slip.
I've agreed with the previous poster, but.... you could make a case for 20/50 in a hot environment. Personally I've always used semi synth 10/40 and had no problems, over many miles and years, in the hot parts of Europe as well as chilly old Blighty. And some high mileage bikes too. But as mentioned, bike specific matters too, don't just chuck in some WalMart crap at $2.99 a bucketful, as some of our American brethren have advocated in the past. It's not big and it's not clever
Thanks for all responses. As for David Reynolds, your term “clunkier” is right in line with what I’m describing. You give me some comfort that the clunkiness may eventually “wear away”. And yes, I always try to “match revs by blipping the throttle”. For Samsgrandad, you’re right – the recommended viscosity is 10W40. I ride mostly in the Spring/Summer/Fall when, here in NM, the daytime temps can be fairly hot. That’s what drove me to SAE 20W50. But I must say that before my first oil change at ~500 miles, with “factory oil”, the gearbox was still noisy/rough. And yes, I have been using “car oil”. I note what you claim about them having “additives which are not compatible with motorcycle wet clutches and cause slip.” For MightyBoosh, as I said – I ride in a warm/hot environment most of the time. Would fully synthetic necessarily be an advantage for this issue?
Yes, l noted your location and figured you had used 20/50 intentionally. My son had similar reservations driving over the Pyrenees when his car hit some pretty high oil temps. Was fine though-modern oils have a destruction point of something like 400 degrees. To clarify-l use semi synth oils. I used Castrol Power, then moved over to Silkolene/Fuchs Super. Always 10/40. Silkolene l found gave best gearshifting. No idea if these are available in US, but in your position l'd be tempted to use something of that ilk to see if it helps. Bit of an expense l know but my feeling is you'd see a benefit . Good luck
Yeh... Automotive oil is hard on motorcycle transmissions. I have made that mistake myself in the past. I also live in a climate like yours [Mohave Desert]. I would use a oil with a higher viscosity rating on the second number, but the first number in the rating is the low temp viscosity. I would not change that. But now I only use oil rated for motorcycle use. ...J.D.
It's not what's in car oil that's causing problems if the clutch doesn't slip. It's what's NOT in the oil that's the problem. Motorcycle specific oils use additives to deal with the high loads and increased sheer from the gearbox. Car oil isn't made for lubricating transmission gears and will thin out in no time.
My 2017 T100 is clunky too. When shifting in first from standstill or when shifting from second to third.
My experience is exactly what Bruno_C mentioned!! I just purchased 4 qts of Valvoline 20W-50 "motorcycle oil) ($6.37/qt at Walmart) and plan to use it with my next oil change, which will be coming up soon. I am cautiously optimistic that the "motorcycle oil" may resolve the clunkiness. I will post back a report. Also, I stumbled onto this August 2021 article by Alex in the U.K. which was interesting and apropos to this discussion: "Can I use car oil in a motorcycle?" https://ridewithpeaks.com/can-i-use...ine oil is packed,motorcycle oil must be used
My 2022 SS is like this, as was my 2020 model, quite clunky from 2-3 but smooth and slick everywhere else. My ZZR has always given a hefty CLUNK on engaging 1st but offers slick changes up through the box and is perfect for clutchless up shifts in the top 3 gears. I've had two GSXR1100's in the past and they both had the sweetest gearbox's on any bike I've ever ridden.
My Bonnie gearbox is one of the best I've had, although max temperature in UK is only about 30C. Its an air/oil cooled model which is possibly the same as yours, although I don't know (water cooled came out in 2017 here). One point on oil, I cannot see any reason not to use fully synthetic oil, readily available for motorcycles here, although I welcome any comment on this from someone more authoritative on the subject.
Imho, it is the design of this gearbox that makes it clunky for 2-3 shifts. Changing oil will not make any significant difference.
Castrol make a 20/50 semi synthetic bike oil.....I would never risk a car oil. I to use 20/50 semi synthetic castrol motor cycle type.....my box it quieter with it. No probs with gear changes. How old is your bike.....any warranty left on it.
UPDATE: After pondering all the noise about oil type, it occurred to me that there must (might) be a better, mechanical explanation for the clunkiness in the gear box. The clutch cable tension came to mind. That factor never occurred to me because (1) the clutch lever action always felt pretty good, (2) at only 2300 miles, the clutch tension should be OK, and (3) when one spends $10,000 for a new Triumph off the showroom floor, wouldn’t one expect that the factory set the cable tensions? So the Owner’s Manual specs 0.80” to 0.120” “free play” in the clutch cable. When I checked mine, the gap looked closer to 3/16” (0.1875”) !! So I tightened it to the tune of about 3 turns. On this morning’s test ride, I can report improvement: Most of the clunkiness (especially on downshifts) has softened to more of a click. Neutral to 1st gear at a stop is still clunkier than I’d like but, again, it’s better. For the hell of it, I intend to try the Valvoline “motorcycle” oil (20W-50) at the next oil change to see if I notice any further improvement
Might be worth checking the slow running speed has been set right too, because that can upset the neutral to first gear change if set too high.
Does anyone know what the knurled "1-2-3-4" wheel is on top of the clutch and front brake levers is? I don't see it addressed anywhere in the Owner's Manual.
My 2022 Speedmaster has had no difference in the “ clunk “ with conventional oil or semi-synthetic when engaging 1’st gear at a stop, however in the upshifts, I believe that the smoothness of the upshifts are related to the rpm of the engine.
Very interesting comment Goldline. Mighty Boosh - I finally found this addressed on p.34 of my "Owner's handbook", which erroneously says "An adjuster is rigged to the front brake and clutch levers (all models except on T100 and Thruxton)." My T100 has it!
