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Tire recommendation for 450L

  • Thread starter Thread starter Tamara
  • Start date Start date
You could get a 130/90 or 130/80 to go on the rim, but I never did, and I would not recommend it. the tire profile becomes distorted and compromised.

From my experience, I would say going on the narrow side would actually be better. The 120/90 tire is a fat tire for that bike, and other models of 400 and 450 were fitted with 110/90, even 100/90 size tires. A 110/90R16 or a 120/80R16 tire would go on your L and do nicely. In either case leaning the bike over in a corner will likely become easier, and I'd be willing to bet that a 120/80 or 110/90 tire will last longer.

As a note, according to the Dennis Kirk help center, a 2.15 can hold anything from a 90 to 120 tire width, but only with aspect ratios of 80 or 90
 
BentRod said:
You could get a 130/90 or 130/80 to go on the rim, but I never did, and I would not recommend it. the tire profile becomes distorted and compromised.

From my experience, I would say going on the narrow side would actually be better. The 120/90 tire is a fat tire for that bike, and other models of 400 and 450 were fitted with 110/90, even 100/90 size tires. A 110/90R16 or a 120/80R16 tire would go on your L and do nicely. In either case leaning the bike over in a corner will likely become easier, and I'd be willing to bet that a 120/80 or 110/90 tire will last longer.

As a note, according to the Dennis Kirk help center, a 2.15 can hold anything from a 90 to 120 tire width, but only with aspect ratios of 80 or 90
Click to expand...

Thanks for the info. I'm thinking of going with the 110 since there seems to be a reasonable selection of tires in that size.
 
A 120/80 would be fine. A little lower profile than a 120/90, which will create higher rpm's during highway cruising. Can't figure out why someone would want to go narrower than the stock 120 size (unless they could save a bunch of money). That IRC 120/90 is a decent tire, and priced competitively, so it seems like the obvious choice but to each their own.
 
Nessism said:
A 120/80 would be fine. A little lower profile than a 120/90, which will create higher rpm's during highway cruising. Can't figure out why someone would want to go narrower than the stock 120 size (unless they could save a bunch of money). That IRC 120/90 is a decent tire, and priced competitively, so it seems like the obvious choice but to each their own.
Click to expand...

I ended up ordering the stock size. Shockingly, the local Suzuki shop was able to get me one for a competitive price and they'll install it once it arrives. I wrench on everything but installing tires.
 
Nessism said:
A 120/80 would be fine. A little lower profile than a 120/90, which will create higher rpm's during highway cruising. Can't figure out why someone would want to go narrower than the stock 120 size ................... but to each their own.
Click to expand...


This is really a good question, and one I am happy to answer.

tire diameters, widths and profiles determine the natural turning radius of a tire at any given lean angle. In a turn, the contact patch of the rear tire will move to the inside as the bike leans, and in this way it will make the angle between the center of gravity and the contact patch less severe. When a wider rear tire is used, this movement of the contact patch is greater, and the angle is reduced further. It follows, logically, that to make any given turn, a wider tire will require the rider to push the bike to a further lean angle. This makes leaning the bike into a corner slightly more difficult, and takes a little more effort.

Getting back to the turning radius of a tire, a wide tire will have to lean more and therefore have a tighter radius. A shorter tire, such as a 70 or 80 aspect ratio, down from a 90, will also tighten the turning radius. This is important if you keep in mind that, in a turn the front tire will make a larger turning circle than the rear tire. The math can get complicated as you work in differences in the lean angle due to the steering geometry, deflection of the suspension, deflection of the tire rubber and sliding, but suffice to say that the radius of the front tire and back tire must be paired. If the back tire is short, for instance, and has too small a turning radius, or the front tire has too large a radius, then one of the tires will have to slide a little, as the bike, rider and corner force a specific turning geometry. In addition to wearing out the tires faster, the sliding will be resisted by the friction between the rubber and the road. The resistance will in turn try to force the bike back upright, to a position where there is no lean, and the differences in tire turning radii do not matter

In my experience I felt that the back tire on the L model was a little on the wide side, and I feel a slightly taller or narrower tire would have performed better for me.


A side note

The wider tire does provide more straight line stability though. A small shift of the center of gravity to the left or right, will cause the contact patch to again, shift left or right, keeping the contact patch nearer the CoG.

Also, these geometries and the pairing of tires has been made much easier by the development of radials, and modern tire profiles. unlike bias ply tires, modern tires are specially designed not only to optimized the contact patch size, but also the movement of the contact patch, and the natural turning radius of the tire.
 
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wow. a really nice plain explanation!
I've got two models of gsx400. The stock tires and rims for each differ, (ie:2x18"dia on one versus 19+17" on the other and indeed, handling is already truly different between the two... I was thinking to switch+try the 18" front from the one bike to replace the stock 19" on the other but I'll pay closer attention now.
... I imagine some chopper builds could turn out very badly without a bit of brain attached!
 
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