Well, I just checked, and they are 6MM OD...I think I am correct in assuming these were made to be an uprade for a much smaller engine...I think my lawnmower has a bigger fuel inlet, lol. Of course I'm wondering if it will really make a difference? when I took off the filter cap, I can see there is a very small hole to allow fuel into the bowl, and a chain is only as strong as it's weakest link, so would improving flow to the filter section really matter? This does make me think of plumbing physics I learned when working with sprinkler systems- circuits usually start large and get smaller to increase fluid velocity to make up for pressure decreaseI have seen these inlets too.
What‘s wrong with them?
They are 8mm, just like your fuel hose.
I would use them and not mess with drilling the carb.
that's what I was thinking...Altho these seem tight...My 34 Datr, they actually rotate in the bore, but I can't get them to come out, but don't leak...I notice on that particular carb, and these I just got, there is a little "ring" around where the fitting is pressed in....almost like they pressed or crimped in a little of the carb body around a barb on the fitting or something to prevent it from coming outon a side note. a lot of X1/9's went up in flames due to the press in fuel fittings (had it happen to mine but got lucky and an extinguisher was at hand) Most race car specs mandate they be removed and replaced with a thread in fitting. (very good idea)
I got one like that decades ago from the place I got my carbs. I'd check with the people supplying carbs, manifolds, etc. Seems like I have seen them on eBay as well. Looks like Pierce Manifolds has a selection:so where would I find this cool little bolt on arm?
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