rear tire size

[leafman60]

Has anyone fitted a 190 on the lemans rear????? Any problems ??? What about a 200???? Also, what is the consensus on tire brand/type?? for sport-touring traction and mileage?????

[Admin Jaap]

[Guest captain nemo]

I have ridden a 190 on a LeMans and thought the bike resisted leaning over. I ride a 170 on my V11 Sport and think it handles perfectly. Some even think my 170 is too fat - in fact most people here in the forum think so. I wouldn't go any wider than a 170.

[Baldini]

Has anyone fitted a 190 on the lemans rear

Why would you wanna do that? V11 5.5" rim is overtyred with 180. Use a 170 improves handling no end. Doesn't look quite so butch mind...

 

KB, Cymru

[Guest Brian Robson]

But while we are on about tyres, I got a really good price for a pair of Pirelli's, I have forgotten the name, but they are the original fitment on the Multistrada.

Soft rubber but with a very deep (7mm) tread. Anyone with a multistrada or experience of these tyres?

[Guest John T]

180 is the correct size for a 5.5 inch rim. A 170 might be too small for this rim, (might)

 

Nemos 4.5 inch rim is way too small for a 170. No way you can use all the tire as it is pinched too much on this rim causing unatural handling traits. His bike would greatly benefit from a 160.

 

My first sport had the skinny rim and 170 tire. No way could you use all the tire and a 1 inch chicken strip was always present.

 

After upgrading to 5.5 inch Dymags and a 180 (recommended size) the bike handled much better. Smoother lean in and handling that was more predictable all the way too the edge.

 

Looks cool, works cool, what else do you need.

[zebulon]

170 is also perfect on 5.5 RIM

 

A 190 or 200 is not usefull and you lost a lot of handling.

Look at the duc 996-998 ...

All the guys put a 180 after killing the 190 that is on brand new bike.

 

Think about the Daytona which is perfect with the 160 no need of 180.

Even with a liberated one with more than 100 HP like mine.

For the "zebulon" aka super 4 i fit a 5.5 rim only because the oz wheels was available in 5.5 . But with the big bore engine i think this is better to find super soft tires, that are really more easy to find in 180

[Guest friz]

I own a scura and when my tyres were gone I put a set of avon pro sieres with a 190 rear it has plenty of room looks great handles super its all in what you perfer!!

[Guest captain nemo]

John T -

 

I never really knew what size rim I had. What you say makes sense - I never have gotten to the edge of my back tire, and lord knows, with summer comming, I don't want a half inch chicken strip. I have to say, though, that I have never noticed any unusual or unpredictable handling. But I really would like a super light rim in the back.

 

Couple questions for you:

 

1. If I kept the 4.5, would a 160 handle better (more edge use) than a 5.5 with your recommended 180? It just seems that an oversized rear tyre would be too 'square' and want to stay vertical.

 

2. If I got an alloy rim and stayed with a 160, wouldn't it be way lighter than a 5.5 with a 180?

 

3. Zeb says choice of nice tyres are better with 180 - is this correct?

 

4. How much is the OZ rim, and are there any comparable rims that might be as light and strong but with better value - cheaper?

 

5. Would a 180/70 jack up the back end more than a 160/70? I would think so - might be another good thing.

[Admin Jaap]

Although I wasn't asked:

 

On the german V11 Forum everybody is convinced a 4,5" rim should have a160 tyre and a 5,5" rim a 170 tyre. A lot of the german V11 riders have turned to these smaller tyres and are very happy campers.

[guzzi323]

I put a 170 on the back of my Scura (5.5' rim) and I love it. the bike turns much more responsively.

[Lex]

Well, you can do almost anything but there are two things to think about:

 

1. All things being equal, the smaller the tire the quicker the handling.

 

2. The closer the profile of the rear tire is to the profile of the front the more easily and smoothly the bike will roll into and out of a lean. Back in the old days (before the mid-seventies) bikes ran the same size or nearly the same size front and rear. Fortunately for us bikes have improved so much in every way that we need a lot more rubber on the ground than a 3.25" (~82 MM) front and a 3.5" (~90 mm) rear. Unfortunately, the experts have decided that anything any wider than a 120 in front causes more problems than it solves. That means we are stuck with mismatched profiles. The smaller the mismatch the better your bike will feel.

 

OK, three things...

 

3. If you don't know this, your tires are a litmus test that will be read by people who know bikes. A wide, smooth tire with wide chicken strips sends a loud, clear message to anybody who knows how to read a tire: "I am either a newbie who knows nothing about bikes or a poser more concerned with looks than performance or both". In either case it suggest riding near you might be a bad idea.

 

If anybody is wondering, my bike has a 4.5" rim and a 160 tire with decent sized chicken strips. The tire also has those little lines on the outer part of the tread from pushing the bike a bit. The message is: "I enjoy riding fairly quickly but I've been to the hospital and didn't like it."

 

You can do anything you want (unless you live in a country where these things are regulated) but paying more money for a tire that will not work as well and makes you look either ignorant or like a poser seems like a poor idea to me.

 

To add a personal opinion, if your tires are saying you are riding much faster than mine you should really think about some track time. Yes, I rode like an idiot on the street for years and got away with it, you might be as lucky. OTOH, riding fast on a track is much more fun and safer. I learned on the track how fast really fast is (I've been passed by three time world champion Freddy Spencer, that is FAST) and how dumb I was for what I had been doing on the street. Just a personal editorial.

 

YMMV,

 

Lex

[Admin Jaap]

3.25" (~82 MM) front and a 3.5" (~90 mm)

Thanks for doing the math!

[Guest John T]

<Captain Nemo pounded on his keyboard and the following questions appeared.>

 

John T -

I have never noticed any unusual or unpredictable handling. But I really would like a super light rim in the back.

 

Cap'n, you won't realize the difference untill you try a proper fitting tire. Hard to explain but the bike bends into corners better, hold the angles better and just "feels" more linear getting into and out of the lean.

 

For a good rundown on how weight effects handling, check out this tech article.

http://www.tawvehicle.com/techwh.htm

 

Huge difference fitting lighter wheels. My Dymags save 10 lbs on the rear, 7lbs up front!

 

<The Captain continued tapping at the keyboard>

 

Couple questions for you:

 

1. If I kept the 4.5, would a 160 handle better (more edge use) than a 5.5 with your recommended 180? It just seems that an oversized rear tyre would be too 'square' and want to stay vertical.

 

It's all about keeping the profile the manufacturer designed into the tire. Change the profile and all bets are off. This article can explain better about tire fitment.

 

http://www.sportrider.com/tech/tires/146_0206_size/

 

Putting a fat tire on a skinny rim (like yours) pinches the tire altering the profile. Putting a skinny tire on a fat rim flattes the profile. Both are bad.

 

Also, the Guzzi is heavier than other sport bikes, I weigh in the 225 lb range and my modified bike puts out as much torque as an RC51 and a little less than an R1. I WANT more meat back there! Highsides are very ugly!!!!!!!!!!!!!!

 

2. If I got an alloy rim and stayed with a 160, wouldn't it be way lighter than a 5.5 with a 180?

 

I can't find the info I had a few years ago, but the difference in weight between a 170 and a 180 was negligible. (just a little more from a 160-180) I think something like 1/2 a pound. Lighter may just give you better "flickability". This may help on a track or if you run really tight roads, but I like alot of rubber on the road during big sweepers while leaned over. If you put lighter wheels, you are way ahead of the game weight wise.

 

 

3. Zeb says choice of nice tyres are better with 180 - is this correct?

Yes, 180 rears are the most common size for these types of tires.

 

4. How much is the OZ rim, and are there any comparable rims that might be as light and strong but with better value - cheaper?

 

Cheaper? I think you'll faint when you hear prices. When I looked for wheels, Dymag was the only company that made wheels for Guzzis. (shafties) Close to 2 grand and a huge headache from Superbike racing in Georgia. (whole other story, stay away from them) Not sure about O.Z. or other companies making wheels for Guzzi, Zeb can probably answer this one.

 

5. Would a 180/70 jack up the back end more than a 160/70? I would think so - might be another good thing.

 

Now your screwing around with tire/frame geometry. Might be a bad thing, but that is a whole topic in itself. I would stay within the range fitted.

Your 170/60 is roughly the same height as a 180 (width)55 (height) so you just get a wider, but not taller tire. This is a good thing.

 

 

Hope this helps in some way. My brain hurts.

[al_roethlisberger]

3.25" (~82 MM) front and a 3.5" (~90 mm)

Thanks for doing the math!

 

 

...I still say it's .47 liter

 

 

So, with a 170 rear on the 5.5 rim, what is the correct profile/aspect ratio one should choose to maintain correct height?

 

al