Tires, rear brake problem, rear tail light

Yank907 · Post by **Yank907** » Fri Oct 27, 2006 2:46 am

I am a new 91 907ie owner and love it.

I found this site yesterday and it has been a wealth of knowledge so far. My first question for you guys is reference tires.

I have looked up the specs it calls for:

rear- 170/60zr17

front- 120/70zr17

My question : Will it be a good idea to try and go with a 180 width tire on the rear and has anyone tired it? I am curious as to the fit and ride with a wider tire on the rear compared to the original.

Also , I this is stupid but I haven't got any experience with motorcycle tires and this is my first bike in 15 years. But, I am assuming the later number behind the width/ is the tire height/profile. If this is the case what would anyone recommend?

Maybe 180/55 for rear? And also is the front spec the best to stick with? I am really just going for the most grip and nice look of a bit wider tire in the rear.

As for the rear brake problem. When the rear brake is applied the brake pedal will not come back up in the original position without me bringing it up with my toe. Any suggestions on a fix or what the problem is and has anyone had the same problem?

Rear tail light suggestion, the euro spec tail light has a stress crack around one of the screw holes. I bought a US spec from ebay a few days back that was removed when the original owner euroed his when it was new, its perfect. I figured it would be a good buy at 100 bucks when the euro are close to $300. However this is just incase I cannot repair the euro without it looking bad. Does anyone have suggestions for repair of a crack in these tail lights and what is the best looking and most effective fix?

Thanks, Todd

DesmoDog · Post by **DesmoDog** » Fri Oct 27, 2006 4:15 am

Hi Todd,

I run a 180 on the back of my bike. I don't remember feeling any difference when I put it on, but that was years ago and I don't ride the bike all that hard anyway.

On a 180/55 17 the 180 is width in mm, the 55 is aspect ratio, and 17 is the diameter of the rim in inches. So on this tire the sidewall would be 180 * 0.55 = 99mm. I forget what the aspect ratio is on mine but I'm pretty sure it's 55.

I wouldn't go with a different size front tire. I had a 55 (50?) on the front of my 900ss for a while and liked the feel of the 60 better.. I also damaged a rim already and going to a shorter sidewall would only make that easier.

No idea on the brake pedal. Make sure the pivot i clean and lubed? Depending in the severity of the crack in the lens, I'd probably just leave it?

persempre907 · Post by **persempre907** » Fri Oct 27, 2006 9:58 am

Hi Todd, welcome.
I have always had the stock 170/60 r17 on my bike.
You can fix the 180/55 r17 on the rear wheel for sure, but I heard that the feeling was worse.
Also, they say that the 120/65 r17 tire is a good choice for the front wheel, but I will not make any change to the stock measures, also because the Italian laws don't allow any change as to the omologation chart.
Ciao

DesmoDog · Post by **DesmoDog** » Fri Oct 27, 2006 11:39 am

persempre907 wrote: Also, they say that the 120/65 r17 tire is a good choice for the front wheel, but I will not make any change to the stock measures

I'm almost certain putting a tire with a larger sidewall on the front will cause interference with the fender... I had to deal with this on my 900ss. Not a major concern, but enough reason for me not to try it on the 907.

Post by **jcslocum** » Fri Oct 27, 2006 12:05 pm

The 180 will slow the steering a little bit, if your sensitive to those kinds of things. The front should be a 120 and the 70 section offers the best protection of the rime from pot holes and damage. As has been mentioned it may hit the fender so you must be aware of this and check the fit very closely. Some tire manufacturers have different profiles for the same tire so; pointy vs. flat. so you may want to chose a tire that has a flatter profile so it doesn't hit.

Good luck!

Yank907 · Post by **Yank907** » Fri Oct 27, 2006 7:35 pm

Thanks guys, I knew this site was gonna have some good advice I may go wider with the rear but the front I will leave stock. Any thoughts on the rear brake sticking?

Finnpaso · Post by **Finnpaso** » Fri Oct 27, 2006 8:28 pm

There is ONLY VERY SMALL difference between 170 and 180 rear tires, mostly its only "look of bike". I used earlier 170 and last 4 tires have been 180. Not so "big thing" and surely U can use 180/55 without any problems. Front U should use normal 120 tire.

Check that master cylinder in rear brake, that it function, like should. There can be also problem in piston/sylinder: shit inside!

Yank907 · Post by **Yank907** » Sat Oct 28, 2006 7:17 am

GOT it , I will try and take it apart and clean it. Tks again

persempre907 · Post by **persempre907** » Sat Oct 28, 2006 7:30 am

Yank907 wrote:GOT it , I will try and take it apart and clean it. Tks again

Have you well bleeded the line? Have you checked the line, the bolts and the washers, perhaps could be a little leak.
Ciao