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I just put a new set of Metzler ME 888 (rear) ME 880 (front) tires on my 2004 Speedie. After replacing the rear tire, it developed a bounce between 55-60 mph in the front. Thinking that meant the front tire needed replacing, we replaced it. Still, there's a bounce in the front end. Wade aligned the forks and adjusted shocks, and checked all the alignments. Still, there persists the annoying front end bounce. Any ideas on what could've caused this simply by replacing the tires? Thanks, oh the enlightened masses.
Karen (first post)

Did you get the wheels balanced? Sorta sounds like the tire might not be sitting true on the rim.

Check your rear tyre carefully, just because its new doesnt mean its good. Look for any abnormalities that could cause the tyre to be out of round, doesnt need to be much to cause a problem. Seems logical its your rear because you didnt have it before, good luck.

To more fully explain what's happened here, as soon as I detected the bounce before replacing the front tire, I took it back to the shop and they checked the tire every which way possible and double balanced it. After replacing the front tire, they put it through pretty much the same routine, carefully checking to ensure it was a good, perfectly round tire. It continues to bounce. Additionally, Wade put the bike on the lift and visually checked the tires and found no defects. I took it for a ride, and it bounced.

Wade has replaced my fork springs with progressive springs and he placed Hagan shocks on the back, but the bike didn't have the bounce until after we replaced the tires. His bike has the same tires with no adverse effects. At this point, we can't find anything wrong with the tires or the bike, but still, at 50-60 mph, the front end continues the bounce. We're at a loss now.

Truly weird!

The unit didn't start to bounce until the rear tire was changed. Where does that lead you???? What could they touch replacing the rear tire? Remember, if it was the chain, why didn't it bounce with the old tire on?

Some things to double check?
1. Bad tire -
2. Balance issue with rear tire
3. Chain too tight
4. Bad/binding Cush Drive rubbers - Remember, the wheel is usually balanced without the cush drive and sprocket installed.

I think Larry came up with the only thing that makes sense. When they changed the tire, they would have had to retension the chain. And if the chain is stiff and dry or worn out, it could definately "jump" a little.

Definitely gonna check that this AM. If that no fix it, I'm gonna either swap my new 888 on Lola with the new 888 on the Speedy, or just buy another tyre.

I dunno, I am running the Metz ME888 rear & ME880 front on my 07 BA & just before I had the 24K service done this spring I noticed a bit of bounce in the front as well at 50+ mph & front end dive when braking. Tire pressure was ok, & I had been running the tires for about 3k miles. So I was thinking it was the fork springs/oil/seals were headed south. Well, as part of the 24K service got them all replaced (progressive fork spring, new seals & oil) & that helped quelched the bounciness to nil. (except when riding on poor road surface, poorly constructed roads). Also replaced the sprocket set & chain & that really helped a bunch too. Maybe your ride needs some TLC maintenance? Just sayin'

A little background on this bike: it's a 2004 model, and I bought it 2-1/2 years ago with only 1,642 miles on him, with about 14,800 on him now. I replaced the tires shortly after I got it since it had sat for so long that the tires had flat spots. I put a new set of Metzeler ME880s on him and ran them for over two years, so the rear was getting low on tread. That was the only problem and it had no bounce then. I got the new tires on him, started toward home, and when I got to 50 mph and up to 60, I noticed a bad bounce in the front. No matter what we do now, the bounce remains. I've gotten ill with my shop where I've serviced my bikes for 8 years over this. I contacted Metzeler and they responded right away that they would pick up the tire and do a warranty evaluation, so the shop ordered a new tire. We'll see as the saga continues if that new tire will work when it comes in. The shop and Wade have both done all they know to do at this point. Thanks, guys, for all the help thus far.

Update : I put that thing on a lift and ran it in first gear. It has a side eccentric about 1/16 " for a distance of about 14 ". Now looking down on the tire from the rear, I can see it sorta wonky. Took chalk like a cutter on a lathe and found a high spot in the center tread out about 1/16 " for about 18 ".

Question is : this be normal ? It might 'splain the strange harmonics around 50 to 60 MPH.

P.S. Chain checks out, rotor OK, wheel OK, has gas, fed my dog, PSI ranged from 38 up to 42 max. , Hagons on soft to medium. I'm all out. I fold. Must be the rubber.