Update on 195/80R 16 car tire

[Yellow Jacket]

If you check out the Nomad "Dark Side" car tire thread you will see where I installed a 195/80R-16 Yokohama tire on my 2006 1600 Nomad a couple of weeks ago.

As I stated in that thread I don't recommend this size since I had to remove the swing-arm brace for clearance.

Since then I have finally had an opportunity to get in some riding on the Interstate and have discovered another issue with this size tire.

All is fine until I get above 70 mph. (The speedometer is now accurate due to the 2.7 inch increase in tire diameter.)

At speeds above 70 mph I am now getting an instability manifested as a wobble or oscillation. If I give a quick push on the handlebars in either direction the bike will wobble back and forth about 3 or 4 times before steadying down. The worst wobble was when I changed lanes at about 70-75 mph from a newly paved lane back onto an unpaved lane. There was a drop of about 1.5 inches. I had a very pronounced wobble which took about 2 or 3 seconds before it damped itself out.

It never felt like I was going to lose control or that it was going to progress rather than damp out. It sort of felt like going over grates or grooved pavement.

I wondered if the increased height at the rear had messed up the steering geometry. The back is now 1.35" higher than stock. After thinking about it for a while I don't think this is the case. This amount of increased height at the rear won't change the rake angle enough to matter in my opinion.

I believe that it's coming from flex in the sidewalls of the rear tire. This tire has a much taller sidewall than the original tire. I was running 40 psi in the rear so I decided to put it up to the max pressure listed on the tire which is 44 psi.

I then got back on the highway and got it up to 75 mph and tried to induce the wobble by giving a quick push on the handlebar and then releasing the pressure. I did still get a wobble but it was diminished quite a bit from that with only 40 psi.

At this time I'm not planning to replace the tire, but I think a 195/65R-16 is probably the maximum size to consider for a 1600 Nomad.

[blowndodge]

Thanks for the Update Bob. I wondered if that much side wall might cause some handling issues with flexing. I wonder if the non uni-directional tread could be be at issue?

[ringadingh]

Do you think the brace you cut out may be causing the swingarm to flex a bit when its on rough or uneven pavement. Just a thought.

Thank for the update Bob. I have considered a car tire when my metzlers wear out. I saw where one of the guys on another thread had ordered a 195/55.R16 to put on.We'll se how that goes. Thanks again for the info.

If you check out the Nomad "Dark Side" car tire thread you will see where I installed a 195/80R-16 Yokohama tire on my 2006 1600 Nomad a couple of weeks ago.

As I stated in that thread I don't recommend this size since I had to remove the swing-arm brace for clearance.

Since then I have finally had an opportunity to get in some riding on the Interstate and have discovered another issue with this size tire.

All is fine until I get above 70 mph. (The speedometer is now accurate due to the 2.7 inch increase in tire diameter.)

At speeds above 70 mph I am now getting an instability manifested as a wobble or oscillation. If I give a quick push on the handlebars in either direction the bike will wobble back and forth about 3 or 4 times before steadying down. The worst wobble was when I changed lanes at about 70-75 mph from a newly paved lane back onto an unpaved lane. There was a drop of about 1.5 inches. I had a very pronounced wobble which took about 2 or 3 seconds before it damped itself out.

It never felt like I was going to lose control or that it was going to progress rather than damp out. It sort of felt like going over grates or grooved pavement.

I wondered if the increased height at the rear had messed up the steering geometry. The back is now 1.35" higher than stock. After thinking about it for a while I don't think this is the case. This amount of increased height at the rear won't change the rake angle enough to matter in my opinion.

I believe that it's coming from flex in the sidewalls of the rear tire. This tire has a much taller sidewall than the original tire. I was running 40 psi in the rear so I decided to put it up to the max pressure listed on the tire which is 44 psi.

I then got back on the highway and got it up to 75 mph and tried to induce the wobble by giving a quick push on the handlebar and then releasing the pressure. I did still get a wobble but it was diminished quite a bit from that with only 40 psi.

At this time I'm not planning to replace the tire, but I think a 195/65R-16 is probably the maximum size to consider for a 1600 Nomad.

Back when I was researching this, I read several times on other boards that most under inflate for best results..... using 28-34 psi on the car rear tires......
You might want to try it just to see?



arkainzeye1

DR001

6/21/06

Goodyear Tripletred

225/55x16

34 psi

VN2K


TooTall

DR002

7/15/06

Goodyear Tripletred

225/60x16


`06 Classic


Top Dawg

DR003

5/1/07

Goodyear Tripletred

205/55x16

26 psi

`04 VN2K


Pegndon

DR004

6/9/07

Fuzion Hri

205/60x16

26 / 32

`06 Classic


Grizz

DR005

6/18/07

Bridgestone Potenza G009

225/60x16


`04 V2K


RGustavsson

DR006

6/25/07

Goodyear Hydragrip

205/60x16

25 psi

`05 VN2000


Titan1958

[Yellow Jacket]

I had started with 40 psi. When I went to 44 psi the wobble is diminished. At Nico's suggestion I tried going to lower pressures. I went down to 36 psi and the wobble gets worse. It looks like the lower the pressure, the worse it is. I going to leave it at 44 psi.

I don't think the removal of the brace is causing any of the wobble. The swing-arm is very stout and I don't think that it can deflect under any of the forces involved in normal riding even with the brace removed.

When I wear this tire out I will probably go to a 195/65R-16 which has a diameter closer to that of a 180/70R-16 Metzeler. Of course if I get the mileage out of this tire that I expect, it may be 2 1/2 years from now!

When I do replace the tire I plan to weld the brace back into place just to get it back to stock.

I'm sorry things aren't going as planned.... thanks from all of us for being a guinea pig. I wish I knew more about this so I could help......

Who else has tried this... I lost track... is it Pablo??

[blowndodge]

Pablo too! Bob who make a 195/65/16 tire?

http://www.camskill.co.uk/products.p...7b128s516p1857

[Yellow Jacket]

Pablo too! Bob who make a 195/65/16 tire?

Tirerack.com shows Continental and Yokohama tires in 195/65/16.
There are probably others as well.

[pablo]

I'm probably going to get my tire installed Wednesday or Thursday this week. It's the 195/55 R16. I was planning on putting about 26 lb of air pressure based on what the other darksiders are doing. I'll let you know how it goes.
Paul

Yeh Pablo.... I've seen the 26 psi over and over.... I wonder why low pressure isn't working for Bob...... Bob... did you try 26 yet?

[blowndodge]

HE SAID WHEN HE KEPT DROPPING PRESSURE THE WOBBLE GOT WORSE!!!!

I know that CME.... but he only dropped to 34 psi......... everyone on the darkside says no more than 28........ gotta be worth a try!?!?


btw........... HAHAHAHHAHA

[Yellow Jacket]

I know that CME.... but he only dropped to 34 psi......... everyone on the darkside says no more than 28........ gotta be worth a try!?!?


btw........... HAHAHAHHAHA

When it stops raining here I will drop to 30 psi and give it a try. If I survive I will then try 28 psi. It'll probably be tomorrow before I can do it.