Topic: Proper Tire Mounting?

[ofreen]

what's the best tire tool to get?

I have changed probably a couple of hundred tires using the 16" Motion Pro tire iron pictured below.  Three is a nice number to have.

[cbjunkie]

nice avatar. my hero...

that tool looks nice - expensive? where do you come by those...anywhere i can walk in/walk out?

[ofreen]

nice avatar. my hero...
that tool looks nice - expensive? where do you come by those...anywhere i can walk in/walk out?

Have you got a Cycle Gear nearby?  They carry one that is similar. I've seen them at other shops, too.   Here is a link.

http://www.cyclegear.com/spgm.cfm?L1=&L2=&L3=&L4=&item=FAI_BRT021

[DiscoEd]

Deflate and make sure that a small piece of inner tube is not pinched under the tire bead.

Maybe, I do have the tube pinched under the rim, I'll have to try again to see if that is the case.

[DiscoEd]

yup gotta watch for pinched tubes or even twisted tubes.

Hey Eldy,
Do you really think that a twisted tube could cause the problem I'm having? I hate to take the tire back off, but I will if I have too.

Regards,
DiscoEd

[DiscoEd]

Not to ask a stupid question, but is the tire the correct size for the rim?

Well, I believe it to be correct. I've mounted a 90/90x19 on the front. I must admit though that the old tire mounted by the PO was a 110/90x19 which I was led to believe was too big in the profile of the tire.

I think that since both tires are for 19" rims that shouldn't be the source of my problems.

[eldar]

Well if a tube is not properly inserted, it could kink or twist in such a way that it cannot properly inflate in that area and will cause a soft(softer) spot on your tire. When riding, this spot whill flex more than the rest of the tire surface causing a bumbing sensation that gets worse the faster you go since you are putting more demands on the tire. this bumb may not be such a huge deal while going straight but on corners..... You get the idea.

[DiscoEd]

Well if a tube is not properly inserted, it could kink or twist in such a way that it cannot properly inflate in that area and will cause a soft(softer) spot on your tire. When riding, this spot whill flex more than the rest of the tire surface causing a bumbing sensation that gets worse the faster you go since you are putting more demands on the tire. this bumb may not be such a huge deal while going straight but on corners..... You get the idea.

Well, Eldy, I finally got back to working on this again. I dismounted the tire and checked the tube for twists, kinks, etc. and could not find any problem. I lubed it up real good and remounted it. Then I put the weight of the bike on the tire plus my weight (sat on tank) and then filled the tire with air. It's better than before but still seems a bit out of round. I'm going to balance it up and ride it around slowly and see what happens. I just don't know what else to do with it.

Regards,
DiscoEd

[eldar]

Have you checked your rim to make sure it is within specs? Spokes may need tightening.

[super pasty white guy]

So, what is the acceptable bead-to-rim variation?  I just had a tire mounted and, given the last round of horror stories, I'd like to make sure the shop did it right?

BTW, anybody know a shop in the Washington DC area that does mounting/balancing cheap?  The best that I could find was $50 per tire (one shop wanted $80).

Dave

[MRieck]

 They can be a real #$%* to seat the bead if you have a lot of rust. What are inflating the tire to trying to seat it?

[Stevearino]

Be careful with your selection of rim lube.  You want something that will be slick to get the bead over and seated, but will dry off without leaving a slick residue.  Water based lube (ie. soap solution) is best.  Trust me, my company sells tons of the stuff to EOM automotive accounts.  Esp with a tube tire, a slick residue can cause the tire to slip on the rim under hard braking or accelleration, shifting the tube in the rim, and cutting the stem.  Fixing a flat is bad enough, stopping with one is something else all together.

[DiscoEd]

Have you checked your rim to make sure it is within specs? Spokes may need tightening.

eldy, I believe that the roundness (runout) of the rim is within 0.010". The wobble is within 0.020". I'm about at my whitsend with this and am thinking about giving in and seeing if a pro can figure it out. I did try driving the bike but you can tell that the tire is not round. it's like riding one of those clown bikes with the square wheels.

Regards,
DiscoEd

[mwvachon]

Best rim lube > spray silicone. Tire tools > Most motorcycle tire irons are satisfactory. When mounting/unmounting my tires, I just lay out an old truck blanket on the driveway and work right down on the ground. I use a generous coating of silicone on all rim/tire contact surfaces. For mounting, start one side of the tire bead over the lip of the rim and work your way around. Once the one bead is in, position the tube and valve stem and just stuff it into the tire. I find a slight bit of pressure in the tube helps this process.  At this point, insure that dot on the tire is lined up with the valve stem. You can also add a bit more air pressure to the inner tube if it's not spreading out within the tire. Not very much, just enough so it starts to get some regular shape. Start the other bead edge into the rim and if it gets too tight, you can try adding a bit more silicone so that the bead slips easier and/or check to see that the opposing bead is pushed in the middle of the rim. Once on, recheck the dot alignment and pressurize! As for balance, my '71 CB750-K1 only required a 5 gram wt. on the rear rim - none on the front!
When doing rims for my restoration, I also re-spoked w/new, so both rims were lined up within .001" for both run-out and alignment.
If you suspect rim being mis-aligned, a cheap & easy way to check right on the bike is to get some medium weight plumbing solder and wrap a length of it around a spot on the fork or swingarm, using the other end as a pointer. Have this 'pointer' lightly seat against the rim side and slowly spin the rim, watching for variations. Move the pointer tip to the inside edge to check the run-out the same way. ALWAYS make small adjustments, checking frequently. Don't forget to loosen opposing spokes where necessary and avoid adjusting the rim toward an off-center position.
Sorry for writing a 'book' here - I just love this stuff!
MV

[old76cr]

Hi. I have the same problem on my K5 with the same tire as Disco bob.  After propping up the front end I deflated the tire and found that the tube was pinched at the valve stem. The reinforced rubber section around the valve  was pushing the tire out in the stem area. After loosening the stem and carefully wedging the tube back into the tire things improved, but I still can't get the tire mounted evenly. When I spin the tire I get about 1\8 inch runout but none on the rim. This results in an irritating vibration at 30 mph plus. Now I've not had a chance to check/change fork oil,  weight etc. but the front end seems very stiff. (P.O. had a fairing and he and his wife were shall we say "husky").  Is this amount of runout normal on a street bike? Should it be absorbed by a properly damped fork? Should I change my name to Mr. Jiggles?

[gar]

[O.K., So I'm trying to get a new Spitfire S11 mounted up on the front of the 550 K1. The problem is that the tire doesn't seem to want to mount up evenly. I've tried inflating, deflating, and reflating to no avail. Even tried bouncing the tire up and down several times. No mater what I try the "bead ring" on the side wall tire doesn't seem to be even around the rim. At one point on the the tire the "bead ring" is right up to the rim edge and at the opposite side of the wheel the "bead ring" is 1/4" away from the rim edge.

When I rotate the tire on the stand, there is about 1/4" + of "out of round" of the tire. I don't think the rim is at fault, as I don't see that kind of play in the rim when checking "out of round" of the rim with a dial indicator

I experienced the exact same thing when I mounted spirfires on my '75 550k last week.  I got the 90/90-19" front, 90/110-18" in rear, highly recommended by other SOHCers and a good match for the 3.25 and 3.75 sizes called for in the manual.

I used 11 1/2 inch tire irons  (set of 2, $11.99, denniskirk) and after much time got them on.  I bounced them , pounded all around with rubber mallet as the common service manual suggested, and tried to get the bead ring to be equidistant all-around the tire.  Nevertheless, the side opposite the valve was off 1-2mm regardless of what I did.  I inflated them to 1+1/2 normal pressure (actually I went to 50+ psi trying to get it to seat well and not be out of round on the one side)  but it did nothing.  I deflated the tire then used a small qty of water with a little soap in it, lightly coating the tire bead area/inside rim.  It was fruitless. BTW the Honda common service manual advises AGAINST using soap.  the CSM goes over this process in detail.  you can download the entire volume -do a search in the tech forum for it.  Glen put the link in a recent posting. 

Regarding having the tires mounted/balanced at the shop.... A friend of mine who is a perpetual bike mechanic and another trusted biker told me they wouldn't bother to bring it in to the shop for balancing.  They had rarely seen MC tires significantly out of balance. (This topic is highy contensious, though :-)

I decided I did the best I could do, remounted the wheels, spun them...they stopped in different places, suggesting adequate balance....then I test drove it. The ride was markedly improved, NO shuddering, wobble,  bouncing, vibration.  It was the best ride I've had on it.  Subsequently I have driven ~70 miles on the tires, at sustained speeds of 50-60mph, peaking at ~70mph, with no untoward effect. 

Moreover, it gave me great satisfaction that I did it myself.  The local Honda shop charges $70/wheel on the bike, $35 each if you just bring in the rims.  I ordered my tires/rim strips/tubes from Dennis Kirk.  Free shipping, cheaper than the dealer. 

[DiscoEd]

Just wanted to give an update on topic...

Ultimately the thing that did the trick for me was (at the suggestion of my father) to spray around rim and bead with silicone spray. I then was able to get tire centered properly on the wheel and it works great! In the U.S. the silicone spray can be found at most NAPA stores. Also, this is not the same as WD40 or other penetrants.

ONE NOTE OF CAUTION! If you attempt this please make sure that you take the time to scrub the wheel and tire extremely well with a slightly soapy solution followed by a very very very very generous rinsing with clean water.

Regards,
DiscoEd