center stand technique

An interesting if slightly dated article on tires. It really does cover a lot of the common tire, rim conundrums.
https://www.motointernational.com/blog/news-and-events/post/sharing-daves-ol-tech-articles-episode-3

I'll throw in that if taken to extremes fat rear tires definitely have a negative effect on handling. 300? stupid wide. Guy was riding with some buds and he was really sweating getting that thing around corners. There may have been lots of factors but it sure looked like the front rear alignment in the transition to the lean changed so much that handling was atrocious But I feel the greatest sin commonly committed is levering wider tires on stock rims.

The 86-89 Yamaha Radian 600 runs 16"s front and rear its' possible they would swap on to an XS....
Tire size (front) 110/90-16-59H
Tire size (rear) 130/90-16 67H


It would be interesting to lever some low profile scooter rubber on those rims bolted to an XS, get you the slammed look and maybe handle pretty well, 'til bits start dragging anyways. Would probably work for the inseam challenged.

YAMAHA YX 600 (86-91) (Radian)
Front Rim Size: 2.50x16
Rear Rim Size: 3.00x16

Recommended Front Tire: K591 , size 100/90-16, 30 PSI
Recommended Rear Tire: K591 , size 130/90-16, 32 PSI

OE Replacement Front Tire: K355F, size 110/90H16, 30 PSI
OE Replacement Rear Tire: K355 , size 130/90H16, 32 PSI
Recommended Front Tire: ME330 , size 100/90-16
Recommended Rear Tire: ME550 , size 130/90-16

This example just reinforces what I've been saying. Here is Yamaha selling a bike about the same size/weight and similar size engine as an XS650. Do they choose a narrow tire for the rear to get that superior handling that some of you suggest. No, their engineers chose to use the same size rear tire that my XS650 Special uses. Its obvious they prefer that width of tire on the back.

Note also that they use a 16" tire, not an 18" tire as used on the XS650 Standard.

I think Yamaha engineers knew a thing or two about wheels and tires, and its shows by the size of rear tire they chose.
 
I think Yamaha engineers knew a thing or two about wheels and tires, and its shows by the size of rear tire they chose.

Just one or two.... as in the only ones available back then!

Back in the day of the "factory chopper", (one of the better oxymorons) fatter tires looked the part.

The engineers I worked with often complained that "Engineering is a slave to Marketing"...

Engineers???????......complain????? :laughing::laughing:

It looks like they "recommended" Dunlops or Mezelers, back then. How many more choices are out there today? :D

But times they are a changin', "Our electronic suspension model's traction control is calibrated to use ______ brand tire." blah, blah, blah.....:laugh:
 
Back in the mid '80s, 16" front wheels were the rage. Combined with a larger rear, usually 18", that didn't work out too well. They may have been fine when a bike was brand new and everything was tight, but as wear on all the components set in, handling problems started cropping up. The designers eventually shelved that idea and went back to larger front wheels. I think 17s are kinda the norm today.
 
The engineers I worked with often complained that "Engineering is a slave to Marketing"...

That is certainly true to a certain extent. It took many years to convert north american car manufacturers from the inferior drum brakes to the superior disc brakes.The engineers knew it was much safer, but the accountants in the marketing section controlled the purse strings.

MotoGP racing has been using 190/65R 16.5 tires on the rear, which obviously are more than capable of getting the job done. So why does Yamaha use a 200/55 ZR 17 on its
YZF-R1M? The marketing guys tell the engineers to jam as big a tire as you can get into the swing arm, so they can sell more bikes.
 
Back in the mid '80s, 16" front wheels were the rage. Combined with a larger rear, usually 18", that didn't work out too well. They may have been fine when a bike was brand new and everything was tight, but as wear on all the components set in, handling problems started cropping up. The designers eventually shelved that idea and went back to larger front wheels. I think 17s are kinda the norm today.

Yes, even MotoGP racing is going to 17" wheels/tires this season. Its because Michelin became the sole tire provider, and they wanted to move from the 16.5", that had been in use, to 17" in order to match up with the street tires that they sell. The racing technology could be more easily transferred over to street tires.
 
Maybe they should bring back antidive forks too.

Yes...gp uses an odd size tire..but let's not forget world Superbike which is also where the r1, zx10, gsxr1000, cbr1000rr, ducati 1199 etc all race is homologation based. Thats where street bike technology comes from. Some gp tech finds its way down like the cross plane crank from the yzm1 to the r1 in 2009. Guess what size of tires... 17

Gp bikes share absolutely nothing with street bikes.(and yes honda does make a replica rc213v now)... nothing. Gp is basically f1. World sbk is race on Sunday sell on Monday. Remember all the 750 cc middleweights? Why do you think they existed and were packed with way more tech than their big cc counterparts.? From 88 to about 2006 wsbk rules said no 4 cyls bigger than 750 cc. Bet most don't even know about the yamaha R7 or honda rc45. Or later on why the rc51 and suzuki tl1000r were conceived.

I can't stand when people think gp bikes are even close to the street bikes. Nothing in common. Not even engine configuration...Sans the r1 and m1 crank design.
 
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Got the 110/80/18 on the 2.5x18 front wheel last night. Compared to a couple 100/90/19 mounted tires it's about 3/4" smaller radius. The same set up on the rear is about 3/8" taller the radius of a 130/90/16 and about the same as a 4.25/85/18 gold seal Dunlop. That dunlop might be a bit, um, experienced! Installed rear profile is narrower than the 16, about the same as the 18. Note; Harley mounts anything from 16" to 21" on their fronts, prolly on the same basic chassis, this might be marketing not engineering driven....
I will mount a new 90/90/21 tire on a rerimmed HS front today. I am kinda looking to build a rear in the same config. Could make for some interesting side by side comparo's.
 
Actually when I bought my Yamaha 650 in the early seventies the thought of tire size never even entered my mind.
I think it was all about marketing. The bike looked great, sounded great.

Yes, that's how it was in the 1970's. When I bought a new 1976 XS500C in 1976, I was young and just amazed with the looks and technology of the bike. I thought a DOHC engine was just amazing, disc brakes on both wheels, and cast wheels really neat. Tires.................I didn't care, as long as they were round was good enough.

Times change though. Nowadays, young kids buying sport bikes expect to see a beefy looking rear tire, because that's what the race bikes have that they watch on TV or read about in magazines, so the manufacturers fill that craving. The logic being, if the bike has a big fat rear tire, it must mean the bike's engine is really powerful.

I think on most sporty bikes sold today, you could subtract 20 or 30 mm from the rear tire width, and that would be what the engineers say is required for good handling,power transfer, etc.. But the marketing guys get involved and the rear tire adds 20 or 30 mm of unnecessary rubber.
 
ALL of this because some dumbass has a problem with getting his bike on the center stand. :shootme:

Its just great when a thread generates 412 views in such a short period. We answered the original question, and the thread just kept growing. Wow, don't you just love the
internet:thumbsup: This the information highway in action.
 
Wink!

20160215_193803.jpg

Off to mount the 90.90.21 tire cause I am STYLIN'!
 
some fronts 2nd from right is flat.

20160216_120108.jpg

21 front

20160216_120139.jpg

So you can see these alternatives would affect use of the center stand. :wink2:
 
I saw a similar thing at the local bike shop a couple years ago.
Tires of wildly varying heights stacked together on the tire rack.
And wondered why they would have them mixed up on there.

Then the parts guy said: "Those are all 17s"...
 
Actually, the secret to easy centre stand use is to have it in neutral, have it exactly vertical, front wheel straight ahead, swing down the stand and ensure both feet of stand are touching the ground, therefore it is vertical, push down with your foot whilst lifting with your arm, done.

If one is travelling with the V Strom, add - dismount the panniers, if there is a slope, park it front wheel uphill.
 
Kind of amazing this thread had 37 replies and no one specifically called out the height to width ratio of the tires as being (the biggest?) difference in handling.
A dirt bike runs very tall tires and low pressures, the tire is expected to act as part of the suspension, absorbing shock is a big part of the tire's duty. Just like with cars, street bike tires have evolved from tall, "inch width" tires, +- 100% ratio, down through 90% - 80% to a modern sport bike 70% - 60% and even 55% ratio of height to width. So you have to pick how you ride, what surfaces you ride on, THEN decide on the tire width and section ratio to best meet those conditions. If you ride smooth roads and go fast through corners; 70 series tires on wide rims are attractive and will help keep the bike stable. If you get off on 2 track and pound over rocks and ruts; a 100 series or inch denominated tire is probably where you are headed to absorb shock and keep your rims from getting dented. Ride one bike to do it all and you end up about where, SHOCK! Yamaha spec'd the OEM rubber later in production, 90 series. Since fashion demands it, in the biggest width you can stuff on it, LOL
 
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