2001 M750 carb - need bolt that screws into emulsion tube

[justin-branam]

Finally got my rebuild kit, and everything was going great.... up until the point that one of the hex head bolts that screws into the end of the emulsion tube was stuck so good, that it sheared off. I had continually sprayed it with PB blaster, wd-40, etc, with no luck. What's done is done m, so long story short, I need a replacement. Know where I can find one? I noticed it appeared hollow. Does this matter? If not, can I just replace it with a regular brass bolt? Anybody know what size it would be?

Image here:

https://drive.google.com/file/d/1gC9gbuHHkzSyYN1Ij64gkhro3LMsB0yU/view?usp=drivesdk

[justin-branam]

I think I may have found a fix. Since it does not appear that the bolt is anything special (PLEASE correct me if I'm wrong), I was able to find a brass flathead bolt the same size, on a dusty shelf, in the back corner of my local hardware store  . The threads are 10-32 in case anyone else is wondering. Can anyone confirm one way or the other if this is a viable solution or not? I got two screws, as I want to make sure both carbs are exactly the same.

Image is here: https://drive.google.com/open?id=1LJrztEolA7NKvsADo5FZi5zkqsHNDv9U

[Speeddog]

I'm pretty sure those screws need to be hollow to allow for needle clearance at closed throttle.

Thread is M5x0.8.

1992 Yamaha TDM850 ran the same carbs, I think 1HX-14565-00-00 is the part number, check with the Yammie dealer.

Powerbarn or other aftermarket carb parts boys may have em.
   

[ducpainter]

I think Nick is correct about the reason, so the hollowing doesn't need to be rocket science, or military contract tolerance.

A resourceful guy would hollow out the hardware store bolts.

[justin-branam]

You guys are correct! Just found out about the needles by trial and error, haha! I also have some good drill bits amd machinery at work. I'll give it a go, but if it doesn't work out, that part number looks like a winner. Thank you very much for the info!!!

[Speeddog]

For limited length of engagement, and non-structural, 10-32 and M5x0.8 can be interchanged.

Suspecting that you bought nice nickel plated emulsion tubes.... I'd say run a M5x0.8 die over your 10-32 screws if they don't play well.

If you've got the desire and the equipment, give it a go!

[NGL_BrSH]

I literally did this yesterday.

Definitely M5x0.8.

I really wanted to make mine out of brass because it's softer than Aluminum. Unfortunately I had trouble finding a donor brass bolt/rod.  If you make the bolt out of steel you run the risk of damaging the Aluminum if you cross thread of don't thread the bolt correctly.
Don't forget some washers or o-rings.