The existing petrol pipe on my 500 is clearly marked as 6mm i/d - it measures around 11.5 mm external diameter. The two pipe lengths are aroun 12" & 9" in length for the twin outlet Petcock.
It does not leak & there were no clips on the pipe that seems to fit quite well. The T piece on the carbs has a diameter of 5mm at the narrow centre section with the two built in flanges/olives measuring 7 mm.
I am minded to replace the pipe as it has gone quite stiff not being as supple as new hose.
I've done a search on this site regarding petrol pipe diameter on the 500 the consensus being it is usually 5.5mm i/d DS does a metre length for £25.90 including postage under p/n 95001-550-0160M no details as to material used.
Trawling e-bay there is Nitrile Braided Hose 5.5 mm i/d 10.5 approx @ £6.02 per meter.
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https://www.ebay.co.uk/itm/203502702708?var=503870585945There is Ethanol Proof E85 Bio Hose (Silicone?) suitable for Diesel or Petrol etc 5.mm i/d @ £27.70 per meter.
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https://www.ebay.co.uk/itm/251726976282?var=550653085114I am at a loss as to what to buy.
