News:

This forum is run by RPM and donations from members.

It is the donations of the members that help offset the operating cost of the forum. The secondary benefit of being a contributing member is the ability to save big during RPM Holiday sales. For more information please check out this link: Membership has its privileges 

Thank you for your support of the all mighty FJ.

Main Menu

160 vs. 180 Tire Width

Started by FJ1100mjk, November 29, 2015, 07:59:33 AM

Previous topic - Next topic

FJ1100mjk

Toying with some ideas, and have found that there's a number of options for 4.5 inch width 17" rims that take a 160 width (possibly 170 too) tire.

I did a some internet surfing about viewpoints on 160 vs. 180 width handling differences. Seems like the 180 hinders turn-in and agility compared to the narrower one, and the 180 is sought after for its wider looks. There are some comments on tire width necessary for a certain bike's power, but the FJ isn't putting out the power that many contemporary bikes are that are sold with 180 width rear tires nowadays, and I'm assuming that tires' construction and durability have come a long ways since the mid-80s.

From what I've seen, the 160 pretty much comes in the same models and compounds that the 180 comes in, so you're covered there if you go the 160 route.

1. A 4.5 inch wide rim is lighter than 5.5 inch wide rim. Less inertial mass, unsprung weight, rolling resistance.

2. FJs were spec'd out with a 150 width, so the 160 is wider, but is closer to the 150 for what Yamaha spec'd out for the chassis geometry of the FJ.

A good number of folks here have gone directly from the old 150 width to the 180 and expounded the virtues of doing so. The difference in handling have been noted, and my thoughts are that the merits are attributed to the lower mass of the new rim when compared to the old anchor FJ one, and of course the new tire's compound and it being a radial instead of bias-ply construction. Factors that would be the same, if you went with a 4.5 inch wide rim and 160 width tire.

Just wondering if anyone out there has gone with the 4.5 inch wide rim and 160 width tire out back, and their thoughts/observations after riding on it. Or have gone from 160 to 180 on any other bike that they've owned.

Thanks!


Platinum Zircon-encrusted Gold Member

Iron Balls #00002175
www.ironballs.com


Arnie

I put a Suzuki 4.5" rear wheel on my FJ back in '98, about 100,000 kms ago.
I have had a number of radial tires on it, all but the current one 160/60s (currently trying a 170)
The change to the handling has been significant, due mainly to the short sidewall height and the radial construction.  I guess the weight difference could have also helped as did the change of shock and ride height.

My other bike is a modern 750 V-twin 'nakid' and came with a 6x17" rear wheel with (choice of) either a 190 or 180 radial.  The handling is much quicker than the FJ, but the bike is also almost 150 lbs lighter, a couple of inches shorter in wheelbase, and much steeper head angle.

These 2 bikes are very different and its difficult to ascribe the handling differences to tire width.

My opinion is that the change to the 17" wheel with a modern radial has been the most significant improvement in the handling of the FJ.  The 160 width tire has adequate load rating (unless you tour with the kitchen sink and you and your pillion are a combined 450 lb plus) and helps make the FJ less ponderous.

Wrap up - The 160 works fine.  If you want a more stylish "phat rear", get a 5.5 and a 180.
Note: If you're an actual racer, use the 160.

Arnie

FJmonkey

I cannot answer your question but I can offer my experience. I went from the stock rear to a 17" x 5.5" rear with a 170/180 wide radial. I did not notice any more difference than the new tire feel. I am not the fastest rider nor am I the slowest around the corners. I have ridden with a few FJowners still running stock wheels and they are quicker than I am. It is not the wheel/tire, its the rider. The biggest difference for me came from suspension changes. This provided more confidence in the feel of the bike in the corners. If you really like the corners then don't put too wide a tire on a wheel, it will pinch the profile and not provide the intended contact patch. Go with radial if you can, choose a tire compound that fits your riding style and enjoy.
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

Derek Young

Hey Marty. Are you planning to change out the front wheel as well?
1986 FJ1200 (R.I.P.)
1991 FJ1200
Nanaimo, British Columbia

FJ1100mjk

Quote from: Derek Young on November 29, 2015, 11:16:52 AM
Hey Marty. Are you planning to change out the front wheel as well?

Derek:

Not sure what I am going to do at the moment. For the time being, I've been looking into a number of options.

If I did go the route of a 17 inch rear rim, I'd do the front too. Why do you ask?

Marty

Platinum Zircon-encrusted Gold Member

Iron Balls #00002175
www.ironballs.com


Hersey289

My preference is the 160. Why? I liked the handling of my old RD350LC so quick steering was a trait i wanted in my '85 FJ. Sure, it isn't an RD but I like it.

My setup:
Front: '87 FZR1000 3.5inch, PR4 120 60 r17 (yes 60 series), '89FJ forks, 0.5inches above the clip on
Rear: '99 YZF600, 5inch, PR4 160 60 r17, Penske shock raised to its max

Its responsive in the corners (Tail of the Dragon, ECSR Boone 2015) yet stable n sweepers and slab riding

Rob

fj johnnie

 As Mark said, the rider is the true limiting factor. I have an FZ1 set up with a 180 rear. Following Mr. Hersey in the rain with his set up was one of the best rides I ever had. The 160 is all the tire you will need. Using the YZF set up is , in my opinion, the best option,  dollar for dollar , as a rear wheel upgrade.

rktmanfj


I can't narrow it down to just the rear wheel swap, as I did the full YZF600r swap at the same time.    :scratch_one-s_head:

However, I did try a 160 tire on the 5" YZF rim first, and on more than one occasion, rode right off the edge of it.
FWIW, I've run thru several 170s on it since then, and it's never been a problem.      :pardon:




Randy T
Indy

Blessed be the LORD my strength, which teacheth my hands to war, and my fingers to fight.
Psalms 144:1

'89 FJ1200
'90 FJ1200
'78 XT500
'88 XT350


oldktmdude

Quote from: not a lib on November 29, 2015, 04:57:26 PM

I can't narrow it down to just the rear wheel swap, as I did the full YZF600r swap at the same time.    :scratch_one-s_head:

However, I did try a 160 tire on the 5" YZF rim first, and on more than one occasion, rode right off the edge of it.
FWIW, I've run thru several 170s on it since then, and it's never been a problem.      :pardon:





A 160 on a 5" rim would have the sidewalls very square in relation to the wheel, causing a sharp edge rather than a radius between the sidewall and the tread. The difference would be like trying to roll a cube along the ground as opposed to a round ball.
1985 FJ1100 x2 (1 sold)
2009 TDM 900
1980 Kawasaki Z1R Mk11 (sold and still regretting it)
1979 Kawasaki Z650 (sold)
1985 Suzuki GSXR 400 x2 (next project)
2001 KTM 520 exc (sold)
2004 GasGas Ec300
1981 Honda CB 900 F (sold)
1989 Kawasaki GPX 600 Adventure

Pat Conlon

Quote from: FJ1100mjk on November 29, 2015, 07:59:33 AM
......There are some comments on tire width necessary for a certain bike's power, but the FJ isn't putting out the power that many contemporary bikes are that are sold with 180 width rear tires nowadays......


I disagree with the above statement.

Marty, let me ask it this way: Can you name me a recent 500 lb.motorcycle that produces 120 rwhp with 80+ft/lbs of torque, that has a 160 rear tire?

I didn't think so.

How about recent motorcycles with aprox. the same power (120hp 80tq) that has 180/55-17 tires?  I could think of 2 quickies: Suzuki Bandit and Yamaha XJR13

Sure, no doubt the FJ would be more nimble on 160's but by today's standards, they are too narrow.  My FJ would be much more nimble on bicycle tires but that does not make it a good idea.

IMHO The minimum rear tire size for 17" rims would be 170/60-17 on a 500+lb. motorcycle with our power output.
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

rktmanfj

Quote from: oldktmdude on November 29, 2015, 08:20:35 PM
Quote from: not a lib on November 29, 2015, 04:57:26 PM

I can't narrow it down to just the rear wheel swap, as I did the full YZF600r swap at the same time.    :scratch_one-s_head:

However, I did try a 160 tire on the 5" YZF rim first, and on more than one occasion, rode right off the edge of it.
FWIW, I've run thru several 170s on it since then, and it's never been a problem.      :pardon:





A 160 on a 5" rim would have the sidewalls very square in relation to the wheel, causing a sharp edge rather than a radius between the sidewall and the tread. The difference would be like trying to roll a cube along the ground as opposed to a round ball.

Sorry, but depending on the tire (I was using Shinko Raven 009), both the 160 and 170 are listed fitments for the 5" YZF600 rim, per the local tire distributor.

Randy T
Indy

Blessed be the LORD my strength, which teacheth my hands to war, and my fingers to fight.
Psalms 144:1

'89 FJ1200
'90 FJ1200
'78 XT500
'88 XT350


aviationfred

Marty,

Here is another perspective. 27 years ago when I bought my first FJ...... we did not have the 180/55/17 option. I jumped from a VF500F to the FJ. With the little Honda, I really didn't need to worry about tire spin when on the throttle. It took a week or so to learn to adjust the brain to wrist control. Spinning the rear tire unintentionally ALWAYS gives me a pucker moment. The stock size 150/80/16 would spin in an instant.

With the 180/55/17 tire, The added contact patch dramatically helps with the tire spin problem. I use the 18t-38t sprockets. I can really get on the throttle and rather than spinning the tire, the front end lifts just a tad. I much rather the front end get a bit light under acceleration, than the rear tire trying to slide out from under me.

Fred
I'm not the fastest FJ rider, I am 'half-fast', the fastest slow guy....

Current
2023 Moto Morini X-Cape 650
2008 VFR800 RC46 Vtec
1996 VFR750 RC36/2
1990 FJ1200 (1297cc) Casper
1990 VFR750 RC36/1 Minnie
1989 FJ1200 Streetfighter
1985 VF500F RC31 Interceptor

Derek Young

Quote from: FJ1100mjk on November 29, 2015, 01:11:06 PM
Quote from: Derek Young on November 29, 2015, 11:16:52 AM
Hey Marty. Are you planning to change out the front wheel as well?

Derek:

Not sure what I am going to do at the moment. For the time being, I've been looking into a number of options.

If I did go the route of a 17 inch rear rim, I'd do the front too. Why do you ask?

Marty


When we talked about wheels at the South Dakota rally you seemed to be pretty happy with the stock sizes. I figured you and Ron would always stick with the stock wheels.
If nothing else, tire selection is a great reason to make the switch.
1986 FJ1200 (R.I.P.)
1991 FJ1200
Nanaimo, British Columbia

Derek Young

Quote from: Pat Conlon on November 29, 2015, 09:25:39 PM
Quote from: FJ1100mjk on November 29, 2015, 07:59:33 AM
......There are some comments on tire width necessary for a certain bike's power, but the FJ isn't putting out the power that many contemporary bikes are that are sold with 180 width rear tires nowadays......


I disagree with the above statement.

Marty, let me ask it this way: Can you name me a recent 500 lb.motorcycle that produces 120 rwhp with 80+ft/lbs of torque, that has a 160 rear tire?

I didn't think so.

How about recent motorcycles with aprox. the same power (120hp 80tq) that has 180/55-17 tires?  I could think of 2 quickies: Suzuki Bandit and Yamaha XJR13

Sure, no doubt the FJ would be more nimble on 160's but by today's standards, they are too narrow.  My FJ would be much more nimble on bicycle tires but that does not make it a good idea.

IMHO The minimum rear tire size for 17" rims would be 170/60-17 on a 500+lb. motorcycle with our power output.
For a reference, Donna's 2006 ninja 650r ran a 160 rear tire and had around 70hp 49 tq. Her 2013 Ninja 1000 runs a 190 rear and has around 136hp 76tq.
1986 FJ1200 (R.I.P.)
1991 FJ1200
Nanaimo, British Columbia

oldktmdude

Quote from: not a lib on November 29, 2015, 09:36:39 PM






  A 160 on a 5" rim would have the sidewalls very square in relation to the wheel, causing a sharp edge rather than a radius between the sidewall and the tread. The difference would be like trying to roll a cube along the ground as opposed to a round ball.


Sorry, but depending on the tire (I was using Shinko Raven 009), both the 160 and 170 are listed fitments for the 5" YZF600 rim, per the local tire distributor.


Sorry, I stand corrected. I was thinking of a 160 on a 5.5" wheel and not of the stated 5"wheel. My apologies. 
1985 FJ1100 x2 (1 sold)
2009 TDM 900
1980 Kawasaki Z1R Mk11 (sold and still regretting it)
1979 Kawasaki Z650 (sold)
1985 Suzuki GSXR 400 x2 (next project)
2001 KTM 520 exc (sold)
2004 GasGas Ec300
1981 Honda CB 900 F (sold)
1989 Kawasaki GPX 600 Adventure