Avoiding flat tires: slime, tire liners & more tire liners.

[commuter ebikes]

A 120/50-26 tire would be 30.72" tall, according to this calculation that I found on the internet:

120/50-26 = 120*.50 = 60 / 25.4 x 2 (2 sidewalls) = 4.72″ + 26″ rim = 30.72″

I have six Cromotors already laced into six Surly Rolling Darryl rims, so it would be a big investment to change wheel types. I may buy one of these moto tires, trim it and use it as a tire liner.

It does look like it would make for a great tire liner http://www.jpcycles.com/product/179-323 :



Vee Rubber makes a motorcycle tube (also sometimes referred to as a tire hose) https://www.amazon.com/Vee-Rubber-Mo.../dp/B00SAFSXLU for the above tire.

I imagine it has a Schrader valve and hopefully a thicker rubber wall than bicycle tubes.





The latest online version of Vee Rubber's motorcycle catalog does not include 26" tubes, so this must be a new product.

Too bad the bicycle tube manufacturers do not yet offer a thorn resistant fat tire tube!

[Alan B]

Some days you just can't win.

I think you could use a moped tire in the rear, which is basically a light motorcycle tire. You might need to change the rim to get it to fit properly. I put about 8000 miles on moped tires, and they are cheap and tough. Thread depth on my Gazelles was 0.375, and that's just the tread part, there's still thick rubber under that. On two occasions in about 3 years a sharp nail managed to fully penetrate the rear tire. Other hazards are less troublesome. I had one flat on my mountain bike that turned out to be a little piece of stainless steel wire from a belted radial. That little steel wire wouldn't have endangered the moped tire. But a long enough sharp nail will puncture it when conditions are right.

Converting to tubeless is reportedly a good way to go. The tires reseal much better than tubes, and you can plug a tire without removing it while on the road.

[JPLabs]

Commuter,

Very interesting work you have done on flat prevention! Extra tire layers, wow.

When calculating tire diameters, you need to consider the rim width. Narrower rims make tires taller. Often, a manufacturer will have an overall diameter listed on one or two specific rim widths, if you can find the specifications page for the tire of interest. Even those numbers are not exact, though. I've had motorcycle tires wind up an inch larger than expected from the specs.

You are really loading that rear tire! If I were you, I would look into adapting moped or motorcycle tires for sure. Meanwhile, maybe try the tubeless route and see how it works for you. I did, on my fatbike. Even running 5-7 PSI around the city, it works well for me. I didn't know I'd had a puncture, but when I changed tires, there was a 1/2 inch blob of sealant plugging a hole. I have Mulefut tubeless rims, which makes tubeless conversion a bit easier and more reliable. They have better rim retention (a square bead lock shape) design to cope with low pressures, and have a rim profile which assists seating the bead with no tube.

I'm using Stan's tape with Stan's latex sealant and Surley Knard tires. Also worked well for Snowshoe tires.

Pinch flats aren't a risk if tubeless. You can run lower pressure more reliably over impacts, if that is a desire for you. As heavy as you are loading that rear, though, don't go too fast with low pressure or you may overheat the tire.

You don't necessarily need to have tubeless rims and tires to do the conversion, if you are adventurous. There are several videos and forum discussions of ways to convert non-tubless tires and wheels to tubeless. Stan's tape is made for the job, but expensive. Some guys have success using packaging tape, duct tape, slit inner tubes, and even Saran Wrap to seal the rims. If you use tape, I would suggest the proper stuff (with acrylic adhesive as I recall), not duct tape, though, as it's a lot of work and you don't want to risk the tape adhesive failing and making a mess. I think there is a carpet tape which someone found is nearly the same, but you need to trim the width. Cheap in bulk if you need to do several wheels, though.

Some guys even mix their own 'homemade latex sealant' with latex mold compound (I think?) from the craft stores. Again, to cut costs. Supposedly quite cheap and effective. Recipe is out there. EDIT: in this giant thread someplace I think: http://forums.mtbr.com/29er-componen...ew-406115.html

One risk, for non-tubless rim and tire combinations made tubeless, is that the tire can 'burp' if run at low pressures. That is, partly open the bead and leak air out fast. Not sure how likely it is, but I do remember seeing warnings about it. Worst case, a poorly retained bead could go flat fast or even dismount, so it's critical to have good bead retention at your operating pressure. With your bikes I don't think you run single digit pressures, so burping probably won't be an issue for you, and the bead joint is probably pretty tight, too. But make sure...

[commuter ebikes]

Thanks for the info, guys. FYI I run my tires near the max pressure listed on the sidewalls. I am swamped at work again so my experimenting will be limited to Sundays for awhile. So far no flat tires (I only ride 11 mi/day), but the very next flat tire will get either a tubeless conversion or a trimmed motorcycle tire as another liner. I will have a lot of opportunities for experimentation.

I would be inclined to use the Stan's tape and Stan's sealant on my existing rims. I need to get my money's worth out of these rims and wheel builds.

[JPLabs]

This option is pretty bulletproof, too:




:p

[commuter ebikes]

Since making this thread, I got another flat from a 2" long wood screw. The screw got through one Mr. Tuffy tire liner, the Surly Lou tire, two old Surly Lou tires being used as tire liners, three old tubes being used as tire liners and the tube. For some reason, this tube had no slime in it.

So the screw penetrated four tubes, three tires and the Mr. Tuffy tire liner. When I repaired it, I added two more old tubes so now I am riding around with the Mr. Tuffy tire liner, three Surly Lou tires and six tubes. I also put in 12 ounces of slime, so we'll see if ten layers of rubber is enough. The tire pressure is 29 psi.

[JPLabs]

Moar Rubber! Yeah!

[Galroc]

Have you considered your tread pattern might not be helping? I use a very smooth tread with no spaces. If ride over something, it shouldn't rotate up and puncture between the treads. It should remain pressed to the ground.

I use Kendra Kross tires with a slime tube. No flats in 400 miles riding in the last few weeks on glass strewn road shoulders. Not sure how frequently people get flats but I have never got one with these tires. <knock on wood>

[Rix Ryds]

You must ride through a construction zone to get so many flats! I think you have taken flat prevention to new heights! Unfortunately, to no avail. There is an answer. In San Antonio, the police have their tires treated at a place here that fills the tires with a non-hardening closed cell foam. Costs about $100 for a car tire. The tires retain all the elasticity and handling qualities of the tire, while making it completely impervious to flats of any kind. They cannot leak, because they have nothing in them that will come out! You can shoot holes in them and still ride on. I'm sure the police in your area do the same thing. A buddy who's a cop let me in on it. I haven't done any of my tires, I went tubeless and haven't had a flat since, but most of my flats were pinch flats, and removing the tube cures that. Nails... not so much!

[JPLabs]

Commuter,

I think goint tubeless with a heavy duty sealing is going to be your best bet.

Not sure if it was mentioned yet, but Rhinotire might be perfect for you, if only there were distributors/installers set up in USA. There aren't, yet, from what I found. Even though it's a USA company, the website seems incomplete, and I couldn't find install info. Maybe they offer the tire treatment there, but they don't seem to be promoting it for USA service.

Service is available now in other countries such as Bahrain, so it's not just vaporware: http://rt.bh/faq/

It's a gooey polymer layer, like I've seen in some automotive runflats such as Continental's Contiseal, IIRC, but they offer service to install on any new or used tires. Said to be popular with off road race teams, etc. It's a gel, not a liquid. Supposedly works for bikes, if you can find someone to install it. Which may be impossible or horribly impractical (Courier to Bahrain and back?)

For bigger leaks, with a DIY (pour it in type liquid goo) you want some chunks in there to help plug holes.

Check out Multiseal, too, it's available with up to 5/8 puncture capability. Tubeless + something like that would be worth trying IMO, and lots cheaper than the Rhinoseal, and available.

Just the HD ATV tubeless Slime with chunks might be an improvement for you. You could add your own 'chunks' to beef up the mix if desired, there's some DIY forum info out there.

[commuter ebikes]

Have you considered your tread pattern might not be helping? I use a very smooth tread with no spaces. If ride over something, it shouldn't rotate up and puncture between the treads. It should remain pressed to the ground.

I use Kendra Kross tires with a slime tube. No flats in 400 miles riding in the last few weeks on glass strewn road shoulders. Not sure how frequently people get flats but I have never got one with these tires. <knock on wood>

This is a good point about a street tread keeping the debris flat. I always use a knobby tread pattern because I am going for that Mad Max look. Street treads for the street would be more practical.

[marcva]

I exchanged emails with Schwalbe, and they commented that their marathon plus mtb is pretty bombproof, you might look into that tire as a foundation

[treolan]

I heard that the Marathon Plus MTB's can perform well in the dirt, loose gravel and packed trails, though they offer a bit rougher ride.

[Hard Tail]

think I’ll chip in with my two bobs worth. I do a 50klm round trip commute each day and my path takes me through an area locally referred to as the Gaza Strip, the bike path is enevitibly paved with broken glass. So my flat tyre observations. They generally come in clusters of three and they are inevitably. Easier to simply accept flats happen, carry a spare new tube and two quick fill bottles. The reality is a flat is another 5 minutes on your ride. Now with that Zen crap out the way, I’m running Maxxis Hookworm tyres these days with Stan’s in the tubes. I running about 40psi front and rear. The Hookworms are hard as hell but on the duel suspension Anthem the ride is still sweet and (touching wood) haven’t had a flat for about six months.
Im dipping my toe into the tubeless realm too although with limited success. The ease of quickly fitting tubes is just hard to beat.

[mopa9000]

think I’ll chip in with my two bobs worth. I do a 50klm round trip commute each day and my path takes me through an area locally referred to as the Gaza Strip, the bike path is enevitibly paved with broken glass. So my flat tyre observations. They generally come in clusters of three and they are inevitably. Easier to simply accept flats happen, carry a spare new tube and two quick fill bottles. The reality is a flat is another 5 minutes on your ride. Now with that Zen crap out the way, I’m running Maxxis Hookworm tyres these days with Stan’s in the tubes. I running about 40psi front and rear. The Hookworms are hard as hell but on the duel suspension Anthem the ride is still sweet and (touching wood) haven’t had a flat for about six months.
Im dipping my toe into the tubeless realm too although with limited success. The ease of quickly fitting tubes is just hard to beat.

I have Stans no more flat rims with Stans no more flat sealant. It will seal small holes. I purchased this bike second hand and haven't done a lot of mileage on it yet. Maybe someone else has used the Stans no more flat system with high mileage that can comment. But so far I'm impressed. We have this double Gee thistle here in Australia and after pulling out 3 each hole sealed. This sealant goes hard as it seals the hole.