• Topics: 38
  • Replies: 545
Nov 30, 2017
North UK

Are the plugs “IX”  or “IA (Real LASER)”  –  I say this because Hyosung 125s don’t enjoy IX plugs for that long.   It’s the LASER or  stock CR8E are what they like most.

Have you had a chance to browse around the shop section as what’s on there is what many of the registered folk on here use , and to the extremes they do eventually see 90 indicated on the dash.

Humbly speaking as a wizard, it is a little overkill to try to mess with the valve heads or boring the cylinders out.   However there is no aftermarket oversized pistons for the vtwin , as i don’t think the crank wants to deal with a big bore kit  (like you see on the Yammy 125s). It’s actually not a bad engine to be fair as it is,  it’s only the weight of the bike that lets it down on the initial take off but it will defo hold down long stretches on the M or A roads better than punny little single cylinder 125s.  Believe i’ve pushed the donor 125 all the way up & down the country on the M1 & M62 , i was pretty surprised coming from a guy who only had a ZZR400 that did 120 at best! and ofcourse the GS500 i recently sold.
90 is good for the hyo. However, i do like your bravery to go to the dark side , not many of us actually hone the cylinders or mess with the valve heads.
You may get yourself custom made titanium valve springs for the cams.  No aftermarket folk do this for Hyosung 125s, so totally a custom job here.


2 pipes (rear and front) joining to 1 pipe to the end can, seems to pull best on 125s with a long exhaust can that has a baffle hole of the size of 10p. I tried a few configurations before.   If doing dual exhausts,  that will look really good i won’t lie , just be sure the cans are full size with a small baffle hole so it isn’t loosing out too much puff out there.  It’s not a 2 stroke , but you’ll be surprised the 4t pulls more with a baffle in than out.

I did make 2 tutorials on the site for carb jetting and the slide mod which you can check out as you browse deeper in the forum

// Meditation doesn't mean you have to sit still....

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