Hi all,
I was thinking to upgrade the v brakes on my son’s 16” wheel Islabike (Cnoc 16) and would need some advice please.

The current Tektros work but, as it is a 2nd/3rd hand bike, they got quite rusty: would need at least replacing the pads, noodles and bolts and looking online I see that for £5-£10 more I could get new brakes, so I though why not?

Current Tektros have 90mm arms, but can’t find anything same length. The closer are:
– Tektro 926AL mini (80mm arm)
– Avid Single Digit 5 (I think around 100-105mm?? but can’t find exact info online)

My thoughts for the two:
Tektros:
– just about enough tire clearance (not a problem for now, but mudguards wouldn’t fit)
– less lever travel require for it to bite
– maybe harder to pull?

Avid:
– maybe arms too long?
– lots of tire clearance
– maybe more lever travel required?

Do you think they would work with the current small brake levers?

Or would I better leave it and just replace the small parts (noodle, etc) ?

Many thanks

What size tyres ? I’ve just put Tektro 926AL on my (road) tandem. With 37c tyres the front is OK, but the rear is virtually touching the tyre. Not a chance of getting a mudguard in there.

It’ll vary with different frames of course, but I think you might have clearance issues with the Tektros.

Hi there, thanks.
The tyres are 16×1.75 newly installed BMX/MTB knobby kind of tyres.
At present (i.e. with 90mm arms brakes) I can fit a 10mm stick between tyre and brake cable and still have a few (4-5?) mm gap.

Have you tried getting in touch with islabikes? Been good with us in the past when weve needed parts.

If the current ones work (and they’re alu so shouldn’t be rusty), then yes. The noodles on our old one are rusty, but actually still work fine, are you sure you need to replace anything other than the pads?

I didn’t even know V-brakes came in different lengths. I swapped V-brakes around between my own bikes and my kids bikes without any issues (Shimano, Avid etc..)

I can’t imagine that 1cm will make any noticeable difference to power and cable travel.

Are you worried about tyre clearance between the brake arms and tyres, or between the straddle wire/noodle ?

Just did some research and number crunching. Aa short pull lever which most kids bikes have pull in the region of 7mm cable at full extension. The difference between 90mm and 100mm is 11%. this equates to less than 1mm extra cable required at the lever. You’ll have more power too….

Just did some research and number crunching. Aa short pull lever which most kids bikes have pull in the region of 7mm cable at full extension. The difference between 90mm and 100mm is 11%. this equates to less than 1mm extra cable required at the lever. You’ll have more power too….

Hey thanks, great stuff – I suspected the difference would be somewhat minimal, but didn’t work out the numbers… Much appreciated.

@aracer: you’re right, the alu arms are in fact fine (i.e. no rust); it’s all the other bits that are rusty (noodle, all the bolts and a bit on the hook where the noodle sits). So yes, strictly speaking the only part that would need replacing would be the pads.
The rusty bits is more that they look a bit neglected.

I did contact Islabike: the 2pads+2arms (arms only, no noodle or anything else it seemed) were around £16 (pads alone are £7.99) which seems pricey when a new set of Tektros/Avids goes for around £12-13…

Oh, and many thanks to you all for the help and feedback 🙂

As above, get the proper Isla ones. Sorted.

OP our youngest has a 16″ Saracen Bolt with a 1999 vintage XT parallel push V on it that works just fine with a child’s lever (fitted because the standard v’s were **** and fell to bits when I took them off to service them/sort the springs out).

Remember at that size the kids only weigh a fraction of what you do so what feels like no friction at all to you with the brake pulled on tight will be enough for a 15-20kg child to pull off big skids! You probably know this already.

Less is more sometimes, particularly with the front brake. Won’t take much extra power to make OTBs more likely (bitter experience of tweaking my daughter’s brakes). I’d go for a like for like swap as much as possible.

The tektro V brakes on my daughter’s bike are now actuated by avid FR7 levers, fitted some fresh pads too.

TBH they are brutally effective she can probably stop more quickly than my bulky arse on a disc braked bike behind her…

I looked around online a little more and in the end found some very nice, honestly price Jagwire parts:
replaced cables and housing, noodles, bolts and (most importantly) pads, all Jagwire.
Incredible difference: brakes have a new life and make for some veeeery long skidmarks and one happy little man!