@Mangiples it seems you're not the only one who's had this issue. There are mentions from Japanese Hunter Cub 125 owners of it happening with the K-Speed Diablo exhaust and other aftermarket parts that share the shock mount. It has also happened with the OEM rubber mounted exhaust though
今年に入ってCT125ハンターカブのマフラー側サスペンションのシャフトが折れる事例が数件耳に入ってた。ここが折れるとは、どういう事だと思いましたよ。(SNSから転載)いろいろ検索してみたら、社外マフラー(K-SPEEDのDiabloが多かった)を付けた車体で発生してました。(SNSから転載)1番に考えたのが、社外マフラーによる振動でシャフトが折れた?2番に考えたのが、取付時にオーバートルクで締めた事でシャフトにクラックが入っての破断です。マフラー側(右)は、サスのシャフトにマフラー固定用延長シャフトを付ける構造。(サス左右の締め付けトルクが44Nで、マフラー取付部分が27N、考えずに締め...
blog-goo-ne-jp.translate.goog
2022年1月、リヤサス取付部のボルドがフレームの根元から折れたという情報がFacebookに投稿され話題にな
motobozzi-com.translate.goog
Here's a YouTuber I follow, Ozu-san, explaining how a shop recently did the frame repair on his:
I have
very little comprehension of what's being said, but from the illustration it looks like the shop may have drilled and tapped both sides of the broken piece, installed a dowel stud, screwed it back together, ground down a bevel or v-groove at the butt joint, and then welded that. If that is what they did, it seems like a pretty weird fix to me, maybe just what they were comfortable with trying?
@m in sc 's suggested fix sounds sturdier to me.
Ozu-san attributes the issue to his extensive customization of the motorcycle and emphasizes that he does not blame Honda for it (he's got a few videos talking about the issue). The exhaust he switched to after the repair, a Dirtfreak Delta 4-S Mini, uses more mounting points than the prior aftermarket one which used one
less mount point than the OEM exhaust, and no rubber mounts. His "long" seat has a bracket that attaches to the shock mount which also looks suspect to me.
Here's someone checking for defects in the mount and then changing their aftermarket exhaust to use a tab welded to the rear rack instead as a preventative measure: