While I've have got some of the better stabilizers on my 07 EGC and it handles well at speed, the bike has been slow getting a bit of the bobble at say 55-65 mph in tight turns that that aren't flat. Lean the bike over and the un-flatness in the road makes the bike dance. I've checked the transmission to frame movement and it was minimal. less than a couple thou. I checked at the swingarm and got maybe 15-20 thou at the 2/3 point from the axle. I decided it was time to replace the swingarm bearings. I was going to try some better ones and tighten up the inner bearing spacers since I knew the stock ones fit was loose on the swingarm pivot shaft. They measure about 0757 ID and a new shaft is about 0.749. IIRC the hole the tranny is about 0.753.
When I pulled part I noticed that the inner bearing spacers were smooth on the flat surface that butts up against the tranny as was the tranny surface. I could see a line in the new pivot axle right where the inner bearing spacer and tranny met. I figure that the spacer was sliding across the tranny surface under load even tho the clamping load is about 5000 lbs. The pivot axle was not at tight as when I did the last assembly to the surfaces may even be wearing down.
I've seen guys add and ream bushing in the tranny and make new spacers that had tighter tolerances than stock but I didn't want to deal with trying to do the same while the tranny was in the frame. SInce the bearing bushing was sliding I figured I'd make new bushings where the flat surface against the tranny was rough. Bushing was turned on a lathe out of 416 stainless (what I had laying around), and center hole reamed to 0.750. After final parting of the material, I used a narrow radius tool and heavy feed by hand to spiral cut only about 0.003 from the surface. See pic. The idea is to allow the bushing to bite into the softer aluminum in the tranny.
I assembled the swingarm and took it for a ride. On my test road, the dancing is almost completely gone. I can do that section of road much faster without issue. I still feel some but everything I have will do the bobble in that section if pushed hard enough. I must say that this modification is the best mod to date. I don't know how long it will last or if there are any issues that will crop up but down the road. The spacers aren't hardened but I don't think the load is that severe as the axle is also supported by an aluminum case. I did replace the rear tire at the same time which also helps. In the picture, you can see the older bearing spacer on the left and that the surface is very flat. New bearing spacer on the right. I was going to try the black bearings but cracked one trying to remove the spacer. I suspect that these bearing will have issues on disassembly even if assembled without cranking so I went with new bearings from Drag specialties that I had gotten from California Phil.
Interesting! We have discussed this a couple times in the past. I wish I still had access to a lathe.
Please keep us posted as you stack on more miles, I think you are on to something.
I figure that the spacer was sliding across the tranny surface under load even tho the clamping load is about 5000 lbs.
SInce the bearing bushing was sliding I figured I'd make new bushings where the flat surface against the tranny was rough. Bushing was turned on a lathe out of 416 stainless (what I had laying around), and center hole reamed to 0.750.
I assembled the swingarm and took it for a ride....
I must say that this modification is the best mod to date.
Found similar myself a few years ago. The swing arm bearings were seized from dry grease, the bushings were pivoting instead on the anti-seize.
i used shim stock instead of turning new inner bushings, and documented it so others could do the same if they wished.
cleaned and relived the bearings so they were once again free.
When I went through the mods the bike handled a bunch better until...
I changed the front tire/wheel. I'd been running an Dunlop E4 on the back and a worn Michelin C2 (130-90-16) up front. The C2 was finally gone and it got replaced with a new E4 (130/ 70-18) on the front. It sorta came back so I pulled the rear swingarm and checking things out. The swingarm bearings were still good but I'd not replaced the rear rubbers. I went ahead and replaced them and rebuilt the rear stabilizer I use and the problem was again pretty much cleared up. I should have gone thorough and replaced everything the first time but it tells me all the components need to be up to snuff for the bike to handle well. The front E4 simply made the steering lighter which fed into the chassis causing the bobble. The E4 also has a center cut that grabs the SoCal freeway rain groves a little making the bike wonder a little. I expect that the best tire combo for this bike will be a E4 in the back and AE in the front.
Last edited by Max Headflow; 06-28-2021 at 07:51 PM.
Reason: wonder a little.
I put an ADD in the local newspaper because EYE lost my BAWL running down the street.
It FLU over a car full of guys in GUERRILLA suits.
It happened about ten past the OUR of 10, EYE NEW that because EYE looked at my watch that EYE got in the MAIL from my NICE. It was OVERDO in that time frame but there was no real PANE waiting for it.
It came on a PLAIN from the west COST. EYE THOUGH it was REEL but I was wrong. It came in several SAXS of burlap. EYE WANDERED ALOUD to myself if what EYE am seeing is WRIGHT?
This is a TAIL of how to use words incorrectly. Don’t be VANE and be that guy!!
Just WOLK right up and explain YOU’RE/YORE self.
12-08-2019 | 10:55 AM
Big issue on cutting the bagger bobble.
