My account on r125forum.com seems to have been deleted so I’m going to carry on here and transfer the last couple of posts..
I’ve had some work changes going on so been having to deal with that lately.. so not really had time to post about stuff, just do it.
Nearly 1k miles on the new cylinder and I’d been feeling with the old baffle in it was too restricted and losing power, and without any it’s still a bit overpiped and was losing the torque at the top end.
So I got some 2.5″ ali bar off ebay and cut a slice off and then made up some sort of baffle on the lathe, which looked more like the sort of diameter I was thinking might be good. One side is a bit tapered bc I was limited with the lathe bits I had, not really done much boring before, new bits on order will bring new possibilities.
Short video running through installing and testing my wideband O2 sensor to try and get the fuelling right on my YZF-R125 with 180cc kit. I was kinda nervous about hacking a big hole in my nice shiny stainless exhaust but I guess that’s part and parcel of getting into the more interesting tuning stuff…
This video is me trying to reassemble the broken motor for my YZF-R125, this time with a 180cc big bore kit. Link for the cylinder I bought (which looked *beautifully* machined): https://www.ebay.co.uk/itm/151763913131
Apart from that I only ended up buying the top cam chain guide and one replacement head bolt (which looked like it was going to round off) and a bunch of oil and filters. I’d bought a new cam chain too but hadn’t realised you have to split the bottom end casing to fit it..and you’re supposed to change the main shaft, cam chain and cam gear as a set, so i guess not this time.
Videos I found helpful for preparing the piston, rings and wrist pin etc:
The first step towards getting my beloved R125 running again is going to be taking the engine out to see what went wrong and whether I can fix it or whether I have to replace it.
If there’s any way I can fix the motor then I’m going to try and do that, and possibly slip a 180cc big bore kit in there too since I probably have to replace the cylinder anyway and my very patient insurance folks have said they will insure it if I go ahead.
ok well as regulars might know I’ve been on a bit of a mission lately to repair the wear-and-tear from the wheelies & drifting practice so far, as well as protect the bike for future wheelie activity.
It’s been hard on the bike, and highlighted any pre-existing weaknesses, but I also learnt a lot about what I want and need from the bike in order to do this in a not entirely half-assed way.
I love the clipon risers I’ve been rocking most of this year. My “ideal comfort position” was with them not even on full height, about half height. It added maybe 1.5″ each side in height and the same in width. It didn’t mess with the aerodynamics too much, but gives excellent control from the slightly wider stance, but you can still get down in the corners when you need to. Nice.
However, not so good for standup wheelies. Angles all wrong, doable but feels unnatural. We don’t have lots of power to play with so I need to try and optimise my position as far as I can. I needed to try and push weight back so she comes up more easily, so I added a bit more height to the clipons, which helped but was higher than I’d like and the angle was still wrong somehow, and the brake reservoir hit on the screen constantly which is super annoying.
This is part 7 of my build series showing progress on my fatty/stretched yamaha Neos project (at last!).
Because it’s been so long this is a bit of a general catch up from my camera roll of photos I took along the way while doing stuff, but didn’t necessarily have the energy to film as well.
In this video things are coming together a bit more and we can start to see the bike take shape and become an actual bike that you can sit on and moves under its own power \o/
Most of this video is about working on the frame and lower panels.
The bike is a 2002 Yamaha Neos, 2 stroke, 50cc Minarelli engine in a stretched, “fatty” style. It’s a regular yamaha scooter with much of the plastics removed, 7×12″ rear rim from a mini-classic, it’s stretched by 18″ and lowered a lot.
This is a bit of a different sort of video for me, so see what you think…
I was testing a bunch of stuff on the bike (manual timing chain tensioner, rebuilt cooling system, stunt cage aero) and also new camera equipment and angles. I ended up shooting this as a test if a camera angle and I kinda liked the footage I got. plus it was a fun ride so thought I’d post it 🙂