adipe

i'm having issues with the inner tube getting cuts by the rim tape which i have cut so that it does not interfere with tire seating;
i'm having issues finding easily a quality butyl inner tube that does not have vulnerabilities - low quality and less resistant to high pressure in these circumstances;

i'm having issues with high pressure - needed to ensure a perfectly seate tire - making dimples in the rim tape;

i'm having 150+kgf DS tension (very small tension variance so it's okay) with the inflated tire because the short spokes on this bike (large hub) permits it and i would not change the Alpine spokes on both DS and NDS flanges that ensure durability to vandalism etc. i want the least vulnerable rear wheel as possible for different reasons;
this high tension compresses the rim so that the tire can be mounted quite easily now using just my hands and no effort with the proper technique;

i don't mind having to use tire levers with a thicker cumulative rim tape.

i'm thinking about adding a 26" tube on the 29" rim so that the ~30mm cut portion would go over the existing tape which does not go over the low bead section so that the butyl would cover all the rim seat and maybe even go a bit above that; it shouldn't climb if in tension (no glued portion of the cut 26" tube, just cut as in half lengthwise);

i guess this would solve all my problems BUT i have to ask: has any of you tried using a butyl rim tape in any of these circumstances?
would the tire be more spongy? it's not an easy thing to do - cutting the 26" inner tube to exact size, mounting the tire etc. etc. etc. so i humbly ask for people in the know about this.

thanks in advance.

shelbyfv

I think if you try tubeless tape of the proper width, your issue will be solved w/o weird kludges.

squirtdad

velox tape

adipe

i won't discuss tubeless at all because i'd rather trust a inner tube mounted in such manner as to ignore it for years and be absolutely invulnerable to sand etc.
see to it that tubeless is more dangerous and more hassle.

i want as much safety and durability as possible.

please don't give offtopic information and also don't ask why a tubeless setup is not to be chosen for a worry free life.
tubeless has its uses for competition, low pressure offroad, relative high maintenance which does not fit my profile.

so... back to the question... what are your experience with a not so thin and also not so rigid butyl layer of tape on top of a relatively high pressure resistant proper tape narrowed down to not interfere with the rim seat.

what are your experiences or thoughts for this setup regardless of your alternatives for it (regardless of other people environments etc.)?

a compressed enough rim that would tolerate a thicker but also less rigid butyl layer of tape that would benefit also in ensuring the tube never gets ghost punctures.

is the less rigid layer going to cause problems? can the butyl layer climb a bit on both rim walls with no issues or does it need to be as accurately fit to the rim as to not climb at all?
thanks.

AnkleWork

Two fixes for the same "problem" -- pick one. [How does the rest of the bicycling world cope?]

adipe

"i want the least vulnerable rear wheel as possible for different reasons"

this wheel can handle 400kgf dynamic loads. i will not lower the tension. i could but i will not. i repaired the wheel and will never ever ever change the spokes nor the high tension.
i will not explain why nor give you my weight or the reasons i want the wheel to remain this durable.

and i'm not like your "rest of the bicycling world". i do not do sports, i am not in your bicycling world. i simply hate to have a lightweight bike that needs an other than hassle free maintenance. i am not your typical cyclist. i hate punctures, any kind of puncture. i even hate the freehub body that has more space than just a few gears. but i'm stuck with it.

i just want to have a setup as resistant to punctures and hassle free as possible.
that having - on my hands right now - no easier alternative than to cut the tube, fit it etc.
i just don't want to experiment before asking and i expect no alternatives proposed. just other people's experience or thoughts about the width fit etc.

you could have read the whole thing before posing as being smart.
so if you cannot give me any answer to my questions just ignore this thread. please.

trailangel

HEY. Listen up. ShelbyFV didn't tell you to go tubeless.... he said to USE TUBELESS TAPE instead of all this nonsense of a cut up tube over the spoke bed and the tire bead.

ThermionicScott 

Hey @adipe, before you accuse other people of poor reading comprehension, how about you make sure you're not guilty? @shelbyfv didn't say to convert to tubeless, he just suggested using tubeless rim tape which is strong and thin. I use it in several tubed setups myself.

adipe

ok, sorry for not understanding it was not a tubeless setup proposed. thanks for pointing it out.

still... any thoughts about the butyl 26" cut tube solution in the 29" rim?...

later edit: tubeless tape is not a cheapy option and also don't want to wait too much or go too many local shops looking for it.

the butyl tube is just waiting for it to be cut to a certain size, i just am not sure about the size. that would be one reason to humbly ask for people in the know if a butyl rim tape layer can climb a bit and not need to be cut to a precise linear width with scissors (it stretches lengthwise and sideways too).

adipe

thanks... and sorry about the initial reaction and my lack of detailing that i'm on a tight budget and reluctant to search or buy a tubeless tape.

AnkleWork

Did you read your own words? You wrote that the spoke tension has obviated your desire to use too-narrow rim tape (you know, the actual problem).



You're welcome and good luck.

terrymorse 

Use a decent commercial rim tape like Velox or Zefal:
in the proper width. Problem solved.

Depressions in the rim tape over a spoke hole is normal and poses no puncture threat to an inner tube.

That is a very high tension, which may exceed the rim manufacturer's recommendation. You may have set yourself up for future rim failure at the spoke holes.

Nonsense. No amount of spoke tension will shrink a rim enough to make a tire easier to mount.

Get some decent cloth rim tape of the correct width, install it. Stop worrying.

adipe

thanks for the last bit.
the spoke tension setup has no connection with the narrow rim tape. the rim tape was messed up from the beginning, before i bought the bike.

i was just saying this:
the compressed rim certainly allows an extra layer of compressible butyl tape
and there would be no issues using levers because anyway the wheel is very hard to get off the bike etc, etc. etc. explanations are irrelevant, the only thing i have not mentioned from the start - sorry, guys and thanks, shelbyfv... is my tight budget and reluctance to consider the alternatives while having yet this solution not cleared up as being bad/good, less or more final one.

so... if you can't say this solution i am still considering for today before making myself busy... please excuse me while i will add you to the ignore list.

we'll ever agree to disagree but now you can know i will neither read nor respond to your comments.
of course... you are free to go about your way but i really am fed up with people being offtopic especially when i explicitly said i am not interested in reading alternatives and making this thread very very long and people posting only and only offtopic.

adipe

not even 165kgf DS on a 36h rear wheel? that's about 1.5x tension and compression on the rim (36h) compared to what people got used to.
and it's not a heavy rim but a rather light one. so...

0.85*18*(165+100)/3.1415 = 1290kgf circumferential - until the tire is mounted and then the spoke tension drops to ~150 DS.
that's 143 MPa for about 88mm as the rim has.
that's about 0.002 strain - 70 GPa modulus.

this would be a gross estimation because the modulus is not linear but it's a strain-stress curve, not a line.
it's still to be considered.
0.615mm towards the hub, a total diameter compression of 1.23mm.

i do not need your recommendations about average spoke tension, you clearly haven't noticed i mentioned from the get go uniform tension as you will not be able to achieve unless maybe once in a while on a unbent rim you have not repaired.

you also don't know crap about the yield strength going higher when achieving 180kgf tension on both flanges with a pressured tire.
the rim tape got dimpled from that thing. i managed to put something to cover and level the dimples but anyway... the tubes in this area i live in are low quality and easily break at the joints they have when being assembled from reclaimed rubber.

next thing will be for you to advise me to leave this place and move in your area.
guess what? that cannot happen today or tomorrow.

i was just looking primarily for other people's experience and secondarily for other people's opinions about this matter regardless of their opinions about the tension i chose to have etc. the fatigue resistance for a given treatment of the rim and environment, and also uniform tension and low distance between spokes.

so... feel free to go about your business.
bye. go ride and don't bother me again. in fact you can just feel free to write anything you want. i'm ok with just adding you to the ignore list.

later edit: 180kgf+ so to bring the rim near it's yield, straighten it and also cold work (strain harden) it doing so.
you only do this if you precisely tuned radial and tension variance.

AnkleWork

Nonsense. "When you find yourself at the bottom of a deep dark hole, drop the shovel."

Davet

Note to self; bring the popcorn

WizardOfBoz

Reading your notes, I'm reminded that in engineering we have what are called "overspecified problems". That is, the specifier wants so many things that there is no feasible way to get them.

Also, take a breath. Re-read what you wrote. It's in a pretty imperious and demanding tone, imho. Lighten up and you'll get better results. Coming into the forum and writing several notes that basically say "I want this, and this, and this", and when you get responses you say "You aren't LISTENING to me!" and "I'm not going to listen to you [that is, I'm adding you to the ignore list]" is not usually a good way to get folks to help you. Has this worked for you in other circumstances? I don't think folks here tolerate it very well.

So again, lighten up, be appreciative of folks that are after all writing to help you, and be less of a jerk. If you do, you'll get help. If you don't, please feel free to add me to your ignore list and I'll do the same.

adipe

it's not an overspecified problem, it's a simple problem/goal:
1. no punctures

it's a simple premise most people missed:
2. i can't be bothered to search for velox, for tubeless tape. the local bike shops i have around only have crap. velox is not in stock, the butyl tape i have from some old times is dirt cheap (zero), i have it near me and i just am not so sure about doing all this work, going on for a ride or two later... only to see myself worked for nothing.

i will lighten up and just ignore future replies to this thread as i have almost zero hopes of finding useful replies except "cheer up" ones.

no offense, and thanks for your positive attitude.

others say they will grab popcorn etc.
nevermind the bollocks.

Davet

Regardless of what others will advise you about your potential fix for your problem, you’ll never know if it will actually work or not until you try your proposal and see if it really works, or not.

shelbyfv

Cutting a 26" tube to make a 700c rim strip may work. I would be concerned that it would fit too loosely and move around. You would have to sacrifice a tube, and even then might not know until you ride it. You might search for Kapton tape. It's pretty much the same as tubeless tape but may be cheaper. Also stranded packing tape, maybe you have some? Really, I can't see anything unique about your situation so if you have a convenient bike shop, whatever they have will work. Good luck.

Davet

It’s gotta be pretty rough getting into fights over the internet on purpose. I’m truly sorry you are the way you are.

terrymorse 

Likewise, feel free to continue with your clumsy engineering and made up problems.

terrymorse 

There's a cheap and easy fix for that, and it doesn't cause punctures.

Zefal Cotton Rim Tape

adipe

yea, a 26" tube has no hassle to it except figuring out the width to be cut because it would be under tension and would not move around sideways, i just am not sure if it would be a better fit with the extra layer going up like wtb advise for tubeless for example. and i am a bit lazy to mount and dismount the wheel as it's not an easy thing to do because the rack compresses the frame as the dropout is wider than what the rear rack is made for. taking the tire off and mounting it again and again by trial and error... meh. no like.

i was thinking that there would be no bad thing to have the slightly compressed butyl (about 0.8mm uncompressed) between the tire and the sidewall but thought to ask your opinions about this.

i will just go the distance and cut it wide and if need be i'll see about narrowing it for a fit with no sidewall climb.

another point to be made - repeating it - the extra layer being compressible, less rigid than usual tape. would it be a good thing if not a bad thing? i guess i'll see how good or bad with my butt on the seat, maybe there would be some more damping under shocks and for a rear wheel i won't mind a strange lateral+vertical mix of flex (not the typical one) in the tire in turns.

anyway... i'll post back after i'll do all this tomorrow. right now i have a patch to dry up - one that's put right on the edge between the segments of the tube made from reclaimed rubber and sold to an eastern country after getting a quality check and failing for the usual people who write reviews to praise or nor some product. imagine reviews for a inner tube made by some big name around... not schwalbe, anyway. and i can't find a schwalbe tube around at local bike shops around here.

no use for kapton as i am happy enough with a crappy tape that needs not do anything else but keep the end soft layer from being pushed into the rim. the soft layer that would not be thin but at least 0.3mm even under compression could ensure a straight fit of the tire. the small remaining dimples will not have too much abrasive effect.

talcum powder does not work too well with the rim tape. butyl to butyl contact will be alright as some people prefer for example a slightly heavier tire liner made of an extra layer of compressed butyl half of a tube between the tire and the inflated thinner tube.

i just want the end result to be as nice as the wheel i tuned/repair which is about 0.1mm radial and lateral (total) runout.
the tire(s) should be able to be snug fit and therefore have a wheel with minimal aggregated runout.

if i made all the effort to bring the wheel to these parameters (low spoke tension variance, low runout, high tension, spokes that i haven't picked - the factory did - having had the initial disadvantage as losing tension easier at conventional tension and now having a bit of an advantage of being able to take larger hits from diverse accidental impacts to them which usually occur more when parked) i just would like to top it up and have a not so nice looking bike - i don't give a crap about other people's perception about it on the street etc. and i don't need to have it scream to be stolen - but a functional bit of bike porn so to speak. a nice ride. like eating popcorn riding it and let the crowd go about their business.

shelbyfv

Be sure to update when you see how it works.