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1Back to top Go down   Sidecar front tyre. Empty Sidecar front tyre. Mon Nov 03, 2014 6:08 pm

sidecar paul

sidecar paul
Life time member
Life time member
Since I built my outfit 26 years ago, I've been using 145x15 and, latterly, 145/65x15 'car' tyres on the front wheel.

I had bought a new Falken 145/65x15 tyre to replace a worn Michelin (32K miles). The wet weather rating for the Falken was 'A' which was the reason for choosing that tyre. 

However, last week I came to fit the new tyre, but after struggling for a couple of hours, I could not get the tyre to seat on the rim. In desperation, I took the wheel to a tyre depot and even they could not do the job; they even risked 100 PSI without success.

So, what to do? I could have refitted the Michelin, which was still legal, go and find a new Michelin (I know their tyres fit my rims), or change to a motorcycle rear tyre as a front fitment. Several sidecar friends have found that a rounded front tyre is far less prone to following road grooves or 'whitelining', than a flat treaded car tyre.

Well I chose the bike tyre option and went for an Avon Venom 140/90x15.

Since last Friday I've covered over 500 miles and the difference is astounding, the rounded tread does not follow any grooved road surfaces, no twitches or wiggles at all. I was actively looking for poor roads just to enjoy the solid feel of the steering. It didn't even 'roll' in, what I call lorry grooves, those indentations in the tarmac caused by heavy vehicles.

I must admit to having been sceptical of the claims of using a round profile front tyre, but now I have experienced it, I won't be going back to car tyres, although I don't expect to get 32000 miles out of the Venom!

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

2Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Mon Nov 03, 2014 6:35 pm

Dai

Dai
Life time member
Life time member
A very close friend currently runs a BMW R1100 outfit but his previous one was a K1100LT with a completely home-built and home-designed chassis, including the leading link front end and a fifteen-inch Smart car wheel on the rear

http://advrider.com/forums/showthread.php?t=294734&highlight=adge&page=261

-about halfway down the page. He's been driving chairs on-and-off for the thirty-odd years I've known him and swears he'll never use a car-type front tyre for all the reasons you've just enumerated above.


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

3Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Tue Nov 04, 2014 6:06 am

Crazy Frog

Crazy Frog
admin
admin
Your comments are very interesting Paul.
A friend here has an K100/Vetter hack with the original front wheel (car wheel on the back) and a K1/EZS with Earls forks and car wheels.
He made exactly the same comment about the handling between the 2 bikes. He found that the rig with the car wheel feel very wiggly when you ride over 100k.
I originally thought that it was due to the difference of geometry between the forks or maybe a worn steering damper.
 I am wondering if you would obtain the same result by installing a bigger car wheel and tire in the front.

I am using 15/135 on the front. Maybe I should try to go back to the original narrower 15/125 originally fitted by EML.


__________________________________________________
Sidecar front tyre. Frog15Sidecar front tyre. Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

4Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Wed Nov 05, 2014 4:06 am

AL-58

AL-58
Life time member
Life time member
I've had 145/65 Bridgestone and Continental fronts. I like the bigger contact patch for the greater grip and better brake performance, but there was always a bit of a wiggle.  145/80 Hankook was very vague.  All of them were a very tight fit and hard to seat the bead.

 Now running a 130/90-15 Bridgestone Exedra.  Very stable, lighter steering but too much throttle will just make it slip across the road if I push it (not that much grip).  It'll do for the moment butwill probably go to a Metzeler or similar instead.

Al


__________________________________________________
'87 K100RS/HRD sidecar (1100 motor)  sc25 

'87 K100RT with Paralever backend

"When I'm too old and too foolish to handle a sidecar I'll buy a Sportsbike"

Sidecar front tyre. K-dogs10
    

5Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Wed Nov 05, 2014 7:32 am

Dai

Dai
Life time member
Life time member
I'm no chair expert but I think your problem with the Bridgestone may be that they are dual carcass construction i.e. the bit in the middle is a lot harder than the shoulders.


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

6Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Wed Nov 05, 2014 2:41 pm

sidecar paul

sidecar paul
Life time member
Life time member
CF, I don't think going to a 125 x 15 would have any advantage, it's still a car tyre with a flat tread and squidgy side walls. There seems to be quite a few 15" bike tyres available, as used with these super-scooters, so if a change were contemplated, I would source one of those.
 
So far, and it's still early days, I'm impressed with the grip from the Avon, in the wet it was much harder to make it 'break away' than my previous Michelin 145/65 15. I am presently running at quite a low pressure, 26 PSI, and I think that helps.

But, as we've said before, sidecarists all have their own ideas and what works for one outfit can be hopeless on another; that's why we love them. :geek:


Sidecar front tyre. Sam_0910

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

7Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Wed Nov 05, 2014 6:06 pm

Crazy Frog

Crazy Frog
admin
admin
Thanks Paul.

I never looked at these "super scooter's tires" before. I am curious to see how many miles you can put on these.
I still have a complete spare set of 15" car tires (I bought 2 sets because it was almost impossible to find them here in Canada), but the scooters one will be a nice option for the future.

CF


__________________________________________________
Sidecar front tyre. Frog15Sidecar front tyre. Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

8Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Mon Dec 22, 2014 11:21 pm

boxermetal

boxermetal
active member
active member
I like a narrow car tire on the front with lower tire pressure for on and off road. I've put 10's of thousands of miles and many different combinations at that seems to be the best.

http://www.boxermetal.com
    

9Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Tue Dec 23, 2014 1:30 am

AL-58

AL-58
Life time member
Life time member
Now that my Bridgestone Exedra has broken in or whatever, it's fine even in the wet.  I can't make it break loose now.  Definitely bike tyres on the front from now on.

Al


__________________________________________________
'87 K100RS/HRD sidecar (1100 motor)  sc25 

'87 K100RT with Paralever backend

"When I'm too old and too foolish to handle a sidecar I'll buy a Sportsbike"

Sidecar front tyre. K-dogs10
    

10Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Tue Dec 23, 2014 5:11 pm

sidecar paul

sidecar paul
Life time member
Life time member
Yes, Al, I'm finding that I'm getting much better wet weather grip as well. Still well impressed.

 I suppose that bike tyres need to be grippier than car tyres and that may have something to do with why they don't last that long!

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

11Back to top Go down   Sidecar front tyre. Empty Letting air out Thu Mar 26, 2015 5:28 pm

touchwoodsden

touchwoodsden
Silver member
Silver member
Hi guys. I just found this thread
I have been speaking to Paul on another thread about other things and in particular, Wasp wheels with car tyres.
The PO of my Wasp parts told me that he had exactly the same problem with the car tyres tram lining.
However what he did (on the recommendation of a noted expert!) Was to reduce the tyre pressure to about 20/22 PSI, and he said it transformed it.
At 25psi it wasnt particularly good he said

We shall see

    

12Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Thu Aug 11, 2016 2:09 pm

halflive

halflive
Silver member
Silver member
Hello Paul,

I'm also running a scooter tire on the front of my sidecar combo, Yes it is an improvement. But the picture of your front wheel looks very interesting. I'm sure BMW never manufactured a 15" front wheel. I do not see any welds or fasteners. Can you help me understand how this wheel is made?

http://halflive.hostei.com
    

13Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Thu Aug 11, 2016 5:00 pm

sidecar paul

sidecar paul
Life time member
Life time member
Halflive, it's a Wasp 15" wheel. They made them for sidecars using the BMW Y spoke pattern for their castings. 
Sadly, no longer available. Sidecar front tyre. 177381

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

14Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Thu Aug 11, 2016 5:34 pm

Crazy Frog

Crazy Frog
admin
admin
On a side note, The maximum width of tires for my front fork is 135.
I was looking at the picture of your fork and understood why.
On your sidecar, the supports for the brake calipers are mounted inside the fork.
Sidecar front tyre. Sam_0910

On the EML, the mounting for the calipers are on the outside and the fork is very tight around the tire. There is a maximum of 10mm space between the disk and the lower part of the fork.
Sidecar front tyre. Img_0110

Today I was looking at installing a Sigma bike speedo and after removing the support for the brake caliper, I found that the perfect place for the sensor. It will be the rods attaching the mud guard to the fork and the magnets can go on the lower part of the brake rotor.
The space between the sensor and the magnet will be perfect without any modification. Why was I looking at a difficult problem when the solution was obvious? scratch


__________________________________________________
Sidecar front tyre. Frog15Sidecar front tyre. Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

15Back to top Go down   Sidecar front tyre. Empty Re: Sidecar front tyre. Thu Aug 11, 2016 6:20 pm

halflive

halflive
Silver member
Silver member
Thanks Paul.
Pity these wheels are not widely available, finding them won't be easy. I'll go for an other option, but keep an eye on Ebay.co.uk. It looks like Wasp used a cut down wheel for the mould, nice job.

http://halflive.hostei.com
    

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