Tyre Losing Air.

[MTBeer]

I have a Spec Ground Control 2bliss on the back that is losing air and I can't find the leak. Been riding with it for 6 months with no problems. I have topped up the sealant, but that didn't help. Can't see any visible signs of a leak. Any suggestions?

[DR ◣◢]

Valve leaking?

What rim?

[SaKiwi]

Pump to max pressure, then put in bath filled with water. Best way to detect a leak. Almost certain it's at the valve. If you wiggle the valve, you should hear air blowing out?

[MTBeer]

how do i check if it is the valve? I used the spit test and didn't see anything.

[MTBeer]

Pump to max pressure, then put in bath filled with water. Best way to detect a leak. Almost certain it's at the valve. If you wiggle the valve, you should hear air blowing out?

ya i was going to do that.

[DR ◣◢]

Is it a proper tubeless rim or a one-time conversion an ol?

[Helpmytrap]

Many possibilities but here are 2 likely scenarios:

1) Damaged rim tape. Sign, sealant and air leaking out between the rim and valve (the hole the valve protrudes from), just redo the rim tape.

2) Dented rim. I misjudged the curb 2 weeks ago and landed my rear wheel firmly on the edge, denting the rim. This then caused air to leak as the beading no longer seated properly. Fixed this by bending the dent out with a "water tang", not sure of the English name.

[MTBeer]

Is it a proper tubeless rim or a one-time conversion an ol?

it was a conversion, but been running it for three years.

[Wannabe]

Many possibilities but here are 2 likely scenarios:

1) Damaged rim tape. Sign, sealant and air leaking out between the rim and valve (the hole the valve protrudes from), just redo the rim tape.

2) Dented rim. I misjudged the curb 2 weeks ago and landed my rear wheel firmly on the edge, denting the rim. This then caused air to leak as the beading no longer seated properly. Fixed this by bending the dent out with a "water tang", not sure of the English name.

 

Waterpump Pliers

[MTBeer]

Many possibilities but here are 2 likely scenarios:

1) Damaged rim tape. Sign, sealant and air leaking out between the rim and valve (the hole the valve protrudes from), just redo the rim tape.

2) Dented rim. I misjudged the curb 2 weeks ago and landed my rear wheel firmly on the edge, denting the rim. This then caused air to leak as the beading no longer seated properly. Fixed this by bending the dent out with a "water tang", not sure of the English name.

thanks. thought i would see some sign of sealant leaking. going to pomp it to 3 bar and see what i see.

[DR ◣◢]

it was a conversion, but been running it for three years.

 

Might be time to change the tape on that wheel and also do some basic maintenance on the rim.

 

Not ideal to bend a rim back to shape with waterpump pliers but it is ok if the dent isn't too bad.

[davem]

I have your air, do you want it back?

[MTBeer]

I have your air, do you want it back?

so you're an oxygen thief?

[davem]

so you're an oxygen thief?

 

Not the oxygen specifically, I have the whole lot.

[Helpmytrap]

Might be time to change the tape on that wheel and also do some basic maintenance on the rim.

 

Not ideal to bend a rim back to shape with waterpump pliers but it is ok if the dent isn't too bad.

I know, but it was bend it back or buy a new rim. They are ZTR Crests, so a relatively soft metal.

[DR ◣◢]

I know, but it was bend it back or buy a new rim. They are ZTR Crests, so a relatively soft metal.

 

If its a minor dent use a shift spanner instead with some cloth wrapped around it and gently wedge it back to shape. Start from the outside and move towards the middle of the dent. Then move to the other side and repeat.

 

Johan will chime in any moment now with the correct procedure