YZF-R125 injector swap

So there’s been a few discussions on the forums recently about different injectors, and I happened to film when I swapped my injector over so figured it might be useful.

It’s a pretty straightforward process…as long as you don’t mess it up.

At which point it would become very complicated. So really don’t do that.

I have a theory – that on a stock R125 which has perhaps a slip-on ((or full exhaust) and a K+n filter, that a 120cc/min injector would make a really cheap, convenient upgrade.

When mine was tuned like that the fuel map was adding about 20% across much of the map. Not all of it but enough for it to potentially make a difference where it matters.

And here’s the link to the 120cc/min injector. As far as I’m aware stock is 100cc/min, so that would give you a 20% bump across the range.I’ll just leave this link here: https://www.aliexpress.com/item/32921…

My problem currently is that I don’t have a stock bike to test the idea on…though I’m hoping i’ve found a volunteer. Watch this space 🙂

2 thoughts on “YZF-R125 injector swap”

    1. at a guess I’d say about 20cc/min flow rate. Not sure what I’m missing here? If you mean runnig-wise or wether you should choose one or the other? I guess bigger injectors are less precises at shorter intervals (lower rpm) so the slightly smaller one may run a little better at low rpms but I doubt there’s much in it. The 160cc one in mine seems to run ok in the low/mids too so i doubt there’s much in it.

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