I see Oponeo have a 120/90x17 E09 Dakar which would work for you. I've used this size in the past and it's ok. At �47 that's cheap.You can also fit a 140/80x17 Eo9 Dakar at �54. Still cheap and I've used this size before too. The 140 is tubless but not a problem.

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Touratech big guard. Yamaha handlebar guards. Pivot Pegz. Yam main stand. Camel Toe. 30 mm risers. 14 tooth front sprocket. Big balls. Old and not wise.