AdamJ
Active member
Anyone ever had or heard of anything like this, FJR or otherwise?
Symptom: when accelerating hard in 2nd (think WFO..), at high rpm (6-7.5k) the bike momentarily loses power. There's a slight mechanical 'chunk' sound coming from the gearbox area when it happens, like a gearshift but much quicker and not as pronounced. It takes a very deliberate WFO roll on to make it happen. No problems whatsoever when riding the bike normally. No problems shifting.
I first noticed it ~ 6 months ago during a 'spirited' ride with some friends, rolling on power on corner exits. Pucker factor high, since it's enough to upset the suspension when it happens with the bike anything other than upright. I was running synthetic oil at the time, and immediately changed it out for conventional (yammi stuff, plus yammi filter). I've put several thousand miles on since going back to conventional. I'm about to take it in and see what the shop thinks, but I'm very skeptical they'll be able to repro it without using a dyno. So I did some 'testing' this morning on an empty country road to try to give them a better description of the problem.
It seems unlikely to be a slipping clutch issue, since it's very abrupt, like a drive train hiccup, with almost no change in engine rpm, more like a pause in climbing rpm's. It feels like the bike is going out and then back in gear somehow. It happens very quickly, probably too quickly for the tach to register any rpm increase. I could not reproduce it in either 1st or 3rd. It only seems to happen following an upshift from 1st to 2nd, with WFO throttle roll on in 2nd. Doing a downshift from 3rd to 2nd, then WFO roll on through 2nd doesn't seem to trigger it.
I'm not a hooligan. The bike has not been abused or raced. The bike has 14.5k miles. My concern is if there's a shift fork or something out of whack, it will eventually get worse, so better to get it taken care of now, but I'm betting the shop will recommend a new clutch, which wouldn't be covered under warranty. I could do that work myself, but skeptical that it's needed, since there's no indication of a slipping clutch.
Symptom: when accelerating hard in 2nd (think WFO..), at high rpm (6-7.5k) the bike momentarily loses power. There's a slight mechanical 'chunk' sound coming from the gearbox area when it happens, like a gearshift but much quicker and not as pronounced. It takes a very deliberate WFO roll on to make it happen. No problems whatsoever when riding the bike normally. No problems shifting.
I first noticed it ~ 6 months ago during a 'spirited' ride with some friends, rolling on power on corner exits. Pucker factor high, since it's enough to upset the suspension when it happens with the bike anything other than upright. I was running synthetic oil at the time, and immediately changed it out for conventional (yammi stuff, plus yammi filter). I've put several thousand miles on since going back to conventional. I'm about to take it in and see what the shop thinks, but I'm very skeptical they'll be able to repro it without using a dyno. So I did some 'testing' this morning on an empty country road to try to give them a better description of the problem.
It seems unlikely to be a slipping clutch issue, since it's very abrupt, like a drive train hiccup, with almost no change in engine rpm, more like a pause in climbing rpm's. It feels like the bike is going out and then back in gear somehow. It happens very quickly, probably too quickly for the tach to register any rpm increase. I could not reproduce it in either 1st or 3rd. It only seems to happen following an upshift from 1st to 2nd, with WFO throttle roll on in 2nd. Doing a downshift from 3rd to 2nd, then WFO roll on through 2nd doesn't seem to trigger it.
I'm not a hooligan. The bike has not been abused or raced. The bike has 14.5k miles. My concern is if there's a shift fork or something out of whack, it will eventually get worse, so better to get it taken care of now, but I'm betting the shop will recommend a new clutch, which wouldn't be covered under warranty. I could do that work myself, but skeptical that it's needed, since there's no indication of a slipping clutch.