Hello everyone, I just installed new Lightech rearsets for my 848, fantastic quality BTW. I made sure the shift lever is pointing straight down and the shift rod is in the same plane (i.e.straight) between the rod ends at the shift lever and rear set pivot point. There is no binding anywhere. Since installing these rearsets, shifiting has been awful. I cant get into neutral at all and shifting is extremely clunky. Going into first feels like the entire transmission is going to drop out of the bike. Its never felt like that before. I am certain my rearsets are set up correctly as described above. I am at a loss to understand why/how the shifting behavior can be so adversely effected.
Post some photos of the linkages. How do the new rearsets compare to the EOM ones from a dimensional point of view? Are the lever lengths broadly equivalent?
Thank you for the reply. Attached are some pics. Sorry the lower fairing is still on but I can say the shift lever is definitely pointing straight down. The new rearsets are set up almost identically to the OEM. The OEM shift rod is 140mm and the Lightech one is 165mm but because dimensionally the rear sets are different, the overall shifter angle is only slightly different. The shifter angle is a bit lower than OEM because the shift rod is a bit too long and because the footpeg is slightly higher. I have a flex my ankle down just a little more than I would like so I already ordered a shorter shift rod but I don't think this would make a difference?
I’d be more interested in the lever throw (the distance the lever has to be moved up or down in order to change gear) before and after. If that has changed by much the shift will feel very different. I usually fit rearsets in order to reduce the throw. Try putting the old rearset back on and measure stuff, so that you can compare when the new one is fitted.
That is actually an excellent point! I just measured the distance from the shifter pivot point to where the rod end of the shift rod is connected. OEM is 23mm and Lightech is 45mm. With a longer moment arm, shift force required will be less but longer travel is needed. My shift lever at the transmission does have the option to move the rod end attachment up closer to the spline shaft so perhaps I will do that to try and balance things out and get closer to the OEM setup. Thoughts?
I think the opposite. The increase in that dimension will reduce the lever throw. You will end up with a lever that hardly has to move in order to change gear. If you reduce the distance at the gearbox end, you will further reduce the lever throw.
EDIT: sorry you meant the footpeg end. You are right. I was thinking about it incorrectly. I need to increase the distance at the transmission end.
this is correct, the further the distance of the rod end pivot point from the shift lever pivot point the bigger the arc that the rod end moves in therefore you get more movement of the shift rod for the same movement in the foot lever. OP, is the height of the lever correct for your foot positioning?
Thank you for the reply. The lever height is a bit low for my foot positioning requiring me to angle my ankle down a bit more than I would like to get under the shifter. Unfortunately, the shift rod (165mm) that came with the rearsets is already fully wound down at both rod ends. I already placed an order for a 155mm shift rod so I can raise the lever more to my liking.
Probably no help whatsoever but I have lightech on my 1098R, I used the standard rod and never had any problems... I thought the supplied rod was just simply too long....?
Hey every comment helps as I'm trying to figure this out! At least for the way I like my foot controls the Lightech supplied shift rod (165mm) is only slightly too long. I personally don't like having to flex my ankle too much to get my foot under the shifter. Similarly, I dont mind lifting my foot a bit when downshifting because I find it helps me push down with more force and be more consistent. I did order a 155mm shift rod because I want to raise the shifter a bit more. I haven't tried the OEM shift rod because it looks way to short at 140mm but it could be worth confirming. I'll take a look.
Are the linkage arms in the correct positions? Having the longer rod could put them in positions that doesn't work properly and bind up. As if they are fighting each other.
ok, put the bike on the rear stand and just tried to change gears manually, remembering to rotate the wheel a bit back and forth between shifts. The results were terrible. With the bike on the rear stand I am getting false neutrals and cant even get into first gear sometimes. I knew even before installing the Lightech rearsets that I would likely have to adjust the shift fork when I do my next oil change because on occasion I would get false neutrals and have difficulty finding neutral but the situation has definitely gotten worse with the new rearsets. Not sure why. Looks like I am going to have to crack open the case sooner than I had wanted to.
I'll politely suggest that you ask Google (or better, a human) about mechanical linkages, the effect of differing 'arm' lengths, mechanical advantage, mechanical gain, basic geometry and so on. You have changed the mechanical linkage that governs the relationship between the gearchange lever and gearchange shaft. If you had trouble selecting neutral or gears before the change, it's not surprising that you may have amplified the problem because you've made a detrimental change to the mechanical relationship. If Google doesn't help, ask a mate who understands mechanisms or just leave it standard.
The sad thing here is that I actually have a degree in mechanical engineering! Now I know why I got a grad degree in finance. Anyway, I took a much closer look at my rearsets today and noticed that the rod end at the rearset looked ever so slightly like it was pointing towards the right side of bike. Because of the length of the shift rod this resulted in the rod end at the transmission shaft pointing 8-9mm too far to the inside (right) of the shift lever. I think this misalignment combined with the already too stiff return spring caused me to miss shifts because of the added force needed to overcome this misalignment. I have now added some washers and adjusted the shift lever along the transmission shaft. Manually shifting using my hand with the bike on a rear stand seems easier and smoother. I will take the bike out for a ride tomorrow to confirm. Thank you to everyone for the input!
Well did you manage to sort it? Like Frazzle mentioned rod too long? I fitted the same Lightech rear sets about a month back to my 848 and used the original rod and I have no issues.
Yes indeed I got it sorted out. The two things I focused on were: Making sure the shift rod was aligned straight from the rearset to the shift lever and Getting the shift rod as close to a 90 degree angle to the shift lever I also changed out the rod ends to some high quality ones from Aurora but I don't think these made any difference other than making me feel better. Moral of the story for me was to make sure the various shift linkage components are properly aligned instead of just eyeballing it.
