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Silver Bullet
03-04-2009, 01:28 PM
dose every one with a c\t get a wobble? if not how do we fix it?

flb_78
03-04-2009, 01:34 PM
I had a wobble. I fixed it with a Works performance shock.

Did you go to the Darkside?

Silver Bullet
03-04-2009, 01:43 PM
I came over,I just had a new shock put on, but it is the stock shock. got the cumo 165-15 looks good works good up to about 80 mph. then the wobble. let the air down to 34-35 and did'nt make any diffrence.:12101:

flb_78
03-04-2009, 02:13 PM
I run my BFG at 32 psi. BigBoyinMS runs his Kuhmo at 42psi. You'll just have to play with the pressures until you find what works for your bike.

pegscraper
03-04-2009, 08:11 PM
I can't keep track of everybody. What tire did you get?

I've heard various things about this, but don't have any real answers. Some have fixed it by tightening the steering bearings. Some by tightening the swing arm bearings. Some apparently with a performance shock. Some by finding just the right air pressure. I've heard some blame it on too soft sidewalls, or on an asymmetrical tread pattern with the grooves slanted all one way across the tire. These latter two go with the tire and little can be done but to get a different tire with a different design. Both the Federal and Kumho are guilty on both counts. We don't have a lot of choices to begin with, and limiting the tire to a symmetrical tread pattern narrows them even further. So far, the only tire I know of with a symmetrical tread pattern is the Mickey Thompson. Possibly the Vredestein is also, I can't remember what it looks like. Good luck.

wizard
03-04-2009, 08:46 PM
I've got the TA Radial. I got a wobble after decelerating hard from 100 mph with 32 lbs in the tire. I started to increase the pressure 1 pound every week after that, and I found my happy spot at 35 psi. I could not tell the difference between 35 to 38 psi, so I stuck with the max pressure printed on the tire. I don't usually ride above 80 mph, but there are times when it is necessary.

Silver Bullet
03-05-2009, 01:55 PM
I have the kuhmo. I guess I got the wrong one . so i will tyry diffrsnt air and hope i find the right pressure. :12101:

flb_78
03-05-2009, 02:38 PM
Did you mount the tire up yourself or did a shop do it for you? I'm just wondering if the bead set straight. I've seen several tires that shook because they did not bead up straight. On my first bike, I had a dealer mount up my first set of tires because I did not know how at the time. The front tire was not mounted straight and after about 1000 miles, the entire front end shook between 30-50. If you want, I could take a gander at it sometime. Every tire has a "mounting line" that can be watched while the tire spins.

BigBoyinMS
03-05-2009, 06:06 PM
Did you mount the tire up yourself or did a shop do it for you? I'm just wondering if the bead set straight.

Might want to look and be sure the beads DID seat. They will hold air even if they don't seat all the way. And it takes a LOT of pressure to seat them! :scared:

Silver Bullet
03-06-2009, 10:22 AM
I think it seated ok it looks like id did we used murphys tire stuff on it . mike down at sharps did it for me.the thin runs farley true . i put it up on a stand and run it up pretty good speed and it is streight as a string.:12101:

gunboat
03-06-2009, 11:05 AM
hi all
i have the wobble's twice. the first time was when i had the me880's. i opened the bike up to 115 mph, then the wobbles started. i normany drive 5 mph over the speed limit all the time. this was a couple years ago when i first bought the rsv. i just drive normal posted speed. the next time it happened was a few months after i installed the c/t. i ran the bike back up to 110-115 mph again. the wobbles started again made it thru again. i have not greased or tighten the steering head bearings. but i have now learned to to stay below 90 mph and i won't have any problems. now i know of a 1'st gen rider, who got the wobbles after passing a 18-wheeler probbley pushing 80-90 mph and he got the wobbles. he had just installed new tires front & back. only been installed a couple hundred miles. he went back home after the weekend rebuilt the front end. hasn't had a problem sense then.
i guess what i'am trying to say is anyone can get the wobbles not just us darksiders. be safe, see ya'll on the road somewhere.
don c. :2cents:

Silver Bullet
03-11-2009, 11:35 AM
well folks ,I don't know if I should have or not....The cuhmo is just fine now and what I did is air it up to 48# . went for a rid and 100 it was still gone. So I called it good enough. I now have about 500 miles onit -some of it two up- and it is doimg good for now. now - what do you all think about that much air???

jack:12101:

pegscraper
03-11-2009, 12:15 PM
Obviously they can withstand it, as they take more than that to seat the beads in the first place. As far as riding on it with that much air, just don't hit a bump or ride it long enough to get the tire warm. They can take that much air, but there's no room left to absorb the impact of a bump. It looks like it was just enough to get the bead to squirm a little and seat better. Glad you got it ironed out.

treeman
03-11-2009, 12:38 PM
I had low speed wobble. New Avons did not help. Had Steering Head tighten A- ok that was at 16,000 miles

Terry Richardson
05-27-2009, 11:13 AM
Hey guys, I just replaced my rear tire with Kunda Kruz and at 70 up she starts to wobble side to side,65 and below smooth as silk. Looks straight as an arrow in the stand. Im running about 40psi. Any ideas?

sarges46
05-27-2009, 03:28 PM
Another thought....I am not sure which tire BigBob had on when he crashed last fall. I think it was the federal. He developed a high speed wobble and didnt recover from it.

Flex of the sidewall and a trailer combined didnt go to helping him recover I think.

Now has a new vstar and his knees are back in the breeze..but I dont think he will go to the dark side again.

clmillsaps
05-28-2009, 02:43 AM
I took the lowers off the front of my RSV! <><

GJHutter
05-30-2009, 02:33 AM
I have an 83 venture and have had a wobble now and then , and it is after i get new tires. I have found that what you think is the frount end is all over the road but it is coming from the rear. So now when I get new tires the first thing I do is to snug the axle nuts on both front and back and snug the hell out of them and the wobble goes away.
Also snug up all the frame bolts, and as for tire psi check the tag on the frame for how much needs to be in the tires I think it is 32 psi front and 40 rear , but all bikes have a tag to tell you the right psi . I do this and the ride is just great:fireman:

footsie
06-07-2009, 07:49 PM
I put the avon cobra radial on the frount and solved all of my problems.

Gregg

SteveW
06-07-2009, 07:58 PM
I just got back from a 1500 mile round trip to South Fl. running 75 to 90 most of the way.
I'm using the Vredestein 155-15 on my rear and with the hack it was a real nice smooth ride.
The Vredestein only has a single ply sidewall and took aroung 90 lbs. to seat on the rim. It has a nice thread design and after the trip it looks like it was just put on I am running 42 lbs. in mine. I think its a keeper.

Keep it between the ditches

ronjolly
11-06-2009, 11:46 AM
Installed a NEXEN 165x80x15 on a RSTD 06 44k and climbing 2 weeks ago started air presure at 32 lbs got a wobble bad with speed over 50 mph . pumped it up to 38 it waz better 45 waz great, feels good in turns no swaying...Best move I made in a long time...
"PRAY FOR OUR TROOPS" and now for FT.Hood Familes

Wolf
11-06-2009, 12:15 PM
This post has convinced me to stay with mc tires. I want nothing to do with a wobble that I may or may not recover from.

BigBoyinMS
11-06-2009, 06:17 PM
This post has convinced me to stay with mc tires. I want nothing to do with a wobble that I may or may not recover from.

You're going to be in a world of hurt when you find out that MC tires will give you just as bad a wobble. (Oops! I just let the cat out of the bag!)

From what I'm finding from reading posts here and on other forums, most (if not all) wobbles come from loose or out of alignment suspension parts, whether they be rear or front. At least tightening or replacing worn suspension parts has cured the wobble issue in a lot of cases. But I also wouldn't disagree that a CT, with it's better grip and slightly less rounded profile, will probably point out those problems a little quicker.

Just saying all that to say that IMHO the CT isn't the cause, it just points out problems quicker. Again, that's just my opinion. :happy34:

Wolf
11-06-2009, 09:33 PM
These guys that had the wobble do not seem to have had the wobble before the tire change....

Carbon_One
11-06-2009, 09:50 PM
The only folks who haven't had any issues with c/t's are us trikers. :thumbsup2: Front tires do get cupping on the sides sooner and will cause vibrations at speed once they get cupped enough thou.
Larry

tsigwing
11-06-2009, 10:22 PM
This post has convinced me to stay with mc tires. I want nothing to do with a wobble that I may or may not recover from.


I've never had a high speed wobble on mine. Then again I drive the speed limit.

Wolf
11-06-2009, 11:01 PM
speed Limit? I thought it was a suggestion.

flb_78
11-06-2009, 11:30 PM
Ive had my Kumho over 100mph.

footsie
11-11-2009, 11:02 AM
The day my mother fell, I ran mine 20 miles up interstate 75 above 100, no problems.

thebighop
11-27-2009, 07:38 PM
I had a high speed wobble with both my BFG T/A Radial, and my 165/80 Kumho.
The wobble went away as I got either broke in and found my sweet spot.
I think it has a lot to do with the sidewalls...they aren't made the same as a MT, and tend to sway a bit....
Once the tire has been ran out a bit...maybe 500 miles...possibly over 1000, and you get the air at the right psi....I think the overall integrity balances out and the sweet spot makes the tire work just right for that particular tire and rider.
I ride aggressively...I had the wobble at 80mph plus on the BFG before breaking in and adjusting the psi. With the Kumho the wobble didn't show until 90mph. After about 500 miles and adjusting the psi down to 32lbs...I can do over 100 and with no wobble.
My break in psi was 45lbs on the BFG, and 38lbs on the Kumho.
I am convinced that each tire, rider and ride style combination is unique. By reading what others are doing, and experimenting a little, you can find a starting point and work into your sweet spot.
Also I think that the more you ride on the CT, the better it's going to feel...or should I say the more you ride on the more you'll get used to it, and it will feel better.
I don't even think about it anymore....At first, I was watching for anything out of the ordinary and trying to analyze what was happening.....now I just ride, and don't even remember half the time that I am on the darkside until someone notices the weird tire on my bike...LOL