-
Enjoy XS650.com? Consider making a donation to help support the site.
XS650.com receives a small share of sales from some links on this page, but direct donations have a much greater impact on keeping this site going.
jets?
- Thread starter jerry67
- Start date
I know some have done it but it's not something I would do. Jets aren't that expensive and they are a precision part. There is a tapered bore leading into the metering hole. The numbers indicate the size but I'm not sure how they relate to an actual measurement, so how much bigger do you drill? And then, how do you mark that newly drilled jet with it's "new" size? When re-jetting these, many times we only go up one size, and that's not much of a change.
You could actually purchase tiny reamers specifically made for re-sizing jets. So it can be done for sure. Whether it is cost effective or sensible is another story. For certain Yamaha models with non-Mikuni carbs (Hitachi, Teikei) it may be a viable option if modifying or tuning these bikes. As for the marking of the modified size, a well organized jet storage box should work.
I also believe that a measuring device used to be a part of those reamer sets, just a long, tapered needle with marks indicating diameters.
Note that the hexagonal Mikuni jets are NOT marked with diameter. i.e a #140 main jet is nowhere near 1.40 mm diameter. The number relates either to area or actual flow, I'm not sure.
I also believe that a measuring device used to be a part of those reamer sets, just a long, tapered needle with marks indicating diameters.
Note that the hexagonal Mikuni jets are NOT marked with diameter. i.e a #140 main jet is nowhere near 1.40 mm diameter. The number relates either to area or actual flow, I'm not sure.
hovel
ol' stupid
I read a long time ago not to exceed 10% of the area of the orifice. If you do the math, this is damn near impossible with a standard drill index, you need honest-to-goodness jet drills, a luxury for the home hobbyist. I have re-sized jets just to get CLOSE to the size I'm going to have to buy, I've even soldered some up and started all over. As 5twins mentioned, the taper leading to the orifice is as important to flow as the orifice size itself.
i was just wondering, but yea $5 for a set is cheap
Yes, if you want to save some money, I suggest doing it elsewhere. I don't even like using aftermarket jets because there's no telling how accurately they've been sized or made. I only use genuine Mikuni jets. If you wanna save some money, paint your bike with a brush or something, lol.
actually not that cheap, used a spray gun to shoot the paint
TJZ662
XS650 Addict
where would you buy genuine jets?
Many get individual jets from Niche Cycle. I usually try to buy them in 4 packs because they can be a little cheaper that way, and I use a lot of them. Lately, I've been finding them on eBay, usually for between $12 and $16 a 4 pack.
Well as 5twins says... make sure they're genuine Mikuni. I don't trust the repops either.
Unfortunately the majority of their carb parts are aftermarket. If anyone has a good Canadian source for Mikuni parts, please post up the info. Shipping from the US is expensive and many vendors won’t ship cross border.
the one going to deal with is "650xs direct" the ship from here in Canada which cuts done my cost, already emailed them about the jets "yes" after market, just have to wait till they get the pilot one back in stock.
Don’t get me wrong, I’ve purchased lots of parts from XS650DIRECT. Great prices and outstanding customer service. I have ordered carb parts from them and in a pinch they can work. I too try to buy OEM Mikuni parts if possible but if I get stuck, will use aftermarket.
TJZ662
XS650 Addict
thanks very much gents. Looking forward to tuning my carbs now.
