Penton Owners Group

General Discussion => Penton Talk => Topic started by: KJDonovan on March 07, 2010, 02:58:31 PM

Title: Front tire question.
Post by: KJDonovan on March 07, 2010, 02:58:31 PM
I have a tire question.  I'm running Kenda Dual Sport F/R K-270 tires on my Jack Piner.  On the front I have a 3.00-21 and it is constantly coming off the bead in a couple of places, unless I over fill (90 psi) with air to pop it back on.  I went as far as pulling it off the rim to make sure all the dimples were still on the rim, and they were.  And the rim is straight.  It's like the tire is just not quite wide enough.  Anyway I was thinking of trying the same model tire but a 3.25-21.  My question is, Is anyone else running 3.25 on the front of their bikes?  

Thanks,

KD


Kevin J. Donovan
Foster, Rhode Island
72 Jack Piner (My Ride)
72 Six Day (Wifes Ride)
Title: Front tire question.
Post by: David Laite on March 07, 2010, 06:20:51 PM
Kevin what rims are on your 'Piner? That's just not right, usually once a bead is seated that's it. 90 psi is dangerous, the maximum pressure to seat the bead is on your sidewall. Use a tire mounting lubricant that turns sticky when it dries.

1973 Penton Six Day
1973 Penton Jackpiner
1982 Yamaha XT200
1982 Yamaha XJ650J Maxim
1984 Husqvarna 400WR
1987 Yamaha YZ490
2005 Honda CRF450R
Title: Front tire question.
Post by: 454MRW on March 07, 2010, 08:05:34 PM
Just out of cusriosity, what pressure are you running the tire at normally when the tire is coming off of the bead? you don't have a slow leak possibly, and it is low when coming off? Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
Title: Front tire question.
Post by: Dwight Rudder on March 07, 2010, 11:48:49 PM
Sounds like the tire has a broken bead.  
Get a new Pirelli MT16 front and while you are at it get a MT16 110/100X18 (400X18) rear to go with it.  Vintage looking but work great even on modern bikes.
Title: Front tire question.
Post by: KJDonovan on March 08, 2010, 12:46:32 PM
Guys,

I am running stock Radeilli rims 62MM wide.  As far as the high pressure, I just pump it up to that to get it to pop back on the bead, but then back it off to 35 psi and run it that.  Maybe just a bad tire (broken bead) as Dwight suggests.  I didn't if anyone else here was running the same tire and experiences similar problems.  Also I was thinking the extra width with a 3.25 would be less likely to pop in like the 3.00.

Thanks,

Kevin J. Donovan
Foster, Rhode Island
72 Jack Piner (My Ride)
72 Six Day (Wifes Ride)
Title: Front tire question.
Post by: VICTOR MONZ on March 08, 2010, 06:03:49 PM
I have real good luck with the Dunlop D756F  80/100 x 21 on my 100, 125 and 175 Pentons with Sun Rims.

15 psi max.....most of the time.

Victor


Again Chaparrel Motorsports in San Bernardino, CA ...good guarantee and delivery.  As long as UPS doesn't leave them on my doorstep at midnight !
Title: Front tire question.
Post by: tomale on March 08, 2010, 06:30:06 PM
15 pounds at the very most,, Maybe on rocky trails but on well prepared track, no more like 12 pounds and on a sandy track, even less...I have been known to run 8 pounds in the back and 9 pounds in the front...

Thom Green,Still crazy after all these years!
76' 250 MC5 (orginal owner)74'
250 hare scrambler (project bike)