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Do your gears "clunk" while downshifting? - Printable Version +- The CB1100 Community Forum (https://cb1100forum.net/forum) +-- Forum: Honda CB1100 Discussions (https://cb1100forum.net/forum/forumdisplay.php?fid=5) +--- Forum: Mechanical & Technical (https://cb1100forum.net/forum/forumdisplay.php?fid=7) +--- Thread: Do your gears "clunk" while downshifting? (/showthread.php?tid=4547) |
RE: Do your gears "clunk" while downshifting? - GoldOxide_imp - 02-11-2019 (02-11-2019, 09:40 AM)Cormanus_imp Wrote: I've just started wearing some new boots too and they've changed my relationship with the gear lever. I notice it more when shifting down, they seem to leave me having more weight on the lever which means it doesn't quite return to the point where it's ready to move down to the next gear. It's taking a bit of getting used to. Interesting comment. I am wondering (seriously) if this is somewhat related to the uncommon "1.5" bounce during the 2-to-1 transition? RE: Do your gears "clunk" while downshifting? - the Ferret - 02-11-2019 I bought new boots to ride the FJR ( they make me taller lol) and I had to move the shift lever. ANd I can't wear them when riding the CB because it really messes up my shifting. I would say if it wasnt an issue before the new boots, that's the place I would look at second. i'd still look at lazy shifting first, because when you are accelerating up thru the gears you are more deliberate than when you are done accelerating and just shifting into the " cruising gear". RE: Do your gears "clunk" while downshifting? - pekingduck - 02-11-2019 With the bike idling in neutral, the crankshaft turns the clutch that rides on the mainshaft. The mainshaft has 1st gear machined into it, and the whole clutch and mainshaft/1st gear are all turning happily at around 665 rpm. When the clutch lever (and RLET) are pulled in, oil friction between the clutch plates causes the mainshaft to continue to spin. Mainshaft 1st gear (12 tooth) is always meshed with the larger 1st gear (38 tooth) on the countershaft. (constant-mesh gearbox) Because the rear wheel is not turning, the countershaft also is not turning. Countershaft 1st gear however, is spinning freely at around 210 rpm When you put it in 1st, gear dogs splined to the stationary countershaft are forced sideways into matching slots on the side of countershaft 1st gear spinning at 210 rpm, locking that free-spinning gear to teh countershaft. CLUNK! Suddenly, both 1st gears, both shafts, and the inner clutch hub have to come to an abrupt halt. That's why the clunk and lurch. RE: Do your gears "clunk" while downshifting? - GoldOxide_imp - 02-11-2019 (02-11-2019, 02:56 PM)pekingduck_imp Wrote: With the bike idling in neutral, the crankshaft turns the clutch that rides on the mainshaft. The mainshaft has 1st gear machined into it, and the whole clutch and mainshaft/1st gear are all turning happily at around 665 rpm. Fascinating how RLET spirit almost appears like another dimension descending upon Forum threads. RE: Do your gears "clunk" while downshifting? - Django - 02-11-2019 (02-11-2019, 08:28 AM)GoldOxide_imp Wrote:(02-11-2019, 06:48 AM)Cormanus_imp Wrote: HR, you’re so right about the clunk when selecting first. The Beemers with dry clutch don't. RE: Do your gears "clunk" while downshifting? - GoldOxide_imp - 02-11-2019 (02-11-2019, 06:54 PM)Django_imp Wrote:(02-11-2019, 08:28 AM)GoldOxide_imp Wrote:(02-11-2019, 06:48 AM)Cormanus_imp Wrote: HR, you’re so right about the clunk when selecting first. The Beemers with dry clutch don't. Right, of course. Good point Django. RE: Do your gears "clunk" while downshifting? - pekingduck - 02-12-2019 No, airhead Beemers with automotive dry clutches don't, but you have to periodically take the gearbox out to lubricate the transmission splines. Just like every car with a dry clutch. Oops, sorry, I meant UNLIKE every car with a dry clutch! RE: Do your gears "clunk" while downshifting? - GoldOxide_imp - 02-12-2019 (02-12-2019, 04:24 AM)pekingduck_imp Wrote: No, airhead Beemers with automotive dry clutches don't, but you have to periodically take the gearbox out to lubricate the transmission splines. Sounds like a PITA PKDuck. Did not know. RE: Do your gears "clunk" while downshifting? - DougsZ28_imp - 07-06-2021 (08-18-2013, 01:40 AM)rjk555_imp Wrote: Greetings to the other CB1100 riders. I wanted to find out of one of the actions on my bike is shared with other riders. My CB "clunks" into gear when I downshift gears - particularly first and second gear. By "clunking" I mean that there is a very physical sensation as the gears transition. The clunk is not limited to instances when the bike is moving and I downshift to engine brake. It happens when the bike is not moving and I downshift as well. Mine clunks up shifting and down shifting. RE: Do your gears "clunk" while downshifting? - jimgl3_imp - 07-08-2021 no, they don't |