Carb mishap, advice needed

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Oct 11, 2021
Messages
8
Reaction score
6
I recently got my Vmax up and running about a month ago and today things toon a big turn for the worse.

I purchased the bike from someone who had let it sit for about a year. After a new battery, tank clean out, new fuel filter and shooting carb cleaner down the top of the carbs, I was able to get tge bike to fire up and run with little issue.

I was at the point of syncing the carbs when and adjusting idle speen when i found a couple of the idle air mix screws were hard to turn and one had the flat head slot stripped.

After getting it "ok" and riding it around for about 200 miles i was still not satisfied with the rough idle and low rpm misfire, so i decided it was time to move forward on replacing the fuel mixture screws. The sticking ones came out with no problem and replacing them was a breeze. The problem child is the front right cab, with the stripped flathead slot. After fighting for a day trying to get a flat head to catch, i decided it was time to bust out the reverse drill bits and extractors and try my luck.

Friends, luck was not with me today. The brass screws drilled through easy enough, however, when it came time to use the extractor, the tip broke and left a ridiculously hard piece of metal in the hole. Try as I might I could not get the extractor bit out, and my finagling with a drill bit has me believing i've ruined the threads holding the screw in place.

I am heart broken and frustrated. I am a patient man who tries to do things the right away, and now I believe the only way to correct this is by replacing the whole carb, which as I'm sure you all may know is a pricey endeavor.

If anyone has any advice or opinions, i am all ears.
 
Unfortunately, it’s a common problem with the V Max.

I experienced the same issue with carburetor no.3

Ended up replacing the carburetor body.

There are members here on the site,that are Carburetor Gurus and will point you in the right direction.
 
Unfortunately, it’s a common problem with the V Max.

I experienced the same issue with carburetor no.3

Ended up replacing the carburetor body.

There are members here on the site,that are Carburetor Gurus and will point you in the right direction.

That's comforting at least. If anyone knows where I can find the carb body, I would very much appreciate it. So far a google search is coming up fruitless
 
Dannymax

Sean Morley

CaptainKyle

Any of these members. Use the 'members' list in the upper left.
 
Yeah, that's the problem with extractors, you need to find a tool that is harder than the one you are trying to remove.

I think the next step is cobalt or more likely tungsten carbide drill bits.

You need to have the carb body in a drill press to prevent the drill wandering.

Once the slot was damaged, I would have applied penetrating fluid over a couple of days and aookuedheat, obviously removing all rubber parts from the body. The carbs being aluminium alloy would expand more than steel or brass so the "grip" on the screw is loosened.... but too late for that it seems :(

BTW with steel stuck inside aluminum alloy, there is an electrochemical method of dissolving the steel, dunno about brass.
 
Does not sound like you care to get way deep into the fix and hearing the history, I’d pull the entire rack to send them for full disassembly and ultrasonic cleaning. Any questionable parts can be changed out and having the carb off the bike is the way to try the A/F mixture screw extraction. A single carb body should be available here from one of the guys here.
 
If you are prepared to put the time and money into it then pretty much anything is possible; question is how much time and money this would be versus another carb body.
As has already been suggested, another body would be the way I'd go.
 
I had the same problem with my Vmax a few years ago, but I was lucky and managed to drill out two of these screws without damaging the original thread. if you don't want to or cannot replace the carb body you have two separate problems here, one is to remove the broken extractor and the second is to repair the thread. For #1 as 02GF74 says you have to use something harder than the extractor. In my opinion you should use a diamond rotary bit in a high rpm tool such as a Dremel to grind away the broken extractor. Here is a link to the type of bits I mean: 30Pc DIAMOND BURR ROTARY TOOL BIT SET Dremel Engraving Tiles Stone Glass Wood 5024763068027 | eBay I have done this many times to remove broken taps and similar. It is difficult not to damage the female thread, but it seems that you have done that already. For #2 you need to get an insert that has the correct female thread for the idle screw (M6 x 0.5mm from memory), and of course whatever external thread you can tap in the carb body. It may be difficult to buy these so you may need to get one made or make it yourself.

The question will then arise about the correct setting for that particular idle screw. By the time you have done all this it is not likely to be the same as the others! you will need to visually assess where the tip of the idle screw is for an undamaged carb, and adjust the new one so that it looks the same.

This is all possible, although rather difficult and time consuming, and if you can afford to replace the carb body that is the better solution as suggested above.
 
All the above suggestion to remove the broken extractor are all very interesting but IMO there is only one viable alternative...Spark Erosion.

You will, of course, need suitable equipment to perform this task and no Smithers, a battery and a bit of wire won't do the job! :rolleyes:

Good ol' e-bay has some.....on second thoughts another carb may be easier and cheaper. o_O :D
 
use a diamond rotary bit in a high rpm tool such as a Dremel to grind away the broken extractor.
Yes, I'd totally overlooked them. I've used them to remake a slot in a screw head as well as remove hex (Allen) bolt heads.

It will take longer but does not require a drill press.
 
I am so thankful you guys are all so knowledgable in this work, and also so quick to respond.

After going over the current state of the carb and looking into the work required VS my skill set, I've reached out to a fellow on here. It looks as though Mr. Dannymax has the exact carb body I need and that we are going to be able to make a deal.

Now that I know we will have this replacement part, I feel like this would be a great time to cut my teeth on this and see if I can get this back to a somewhat useable state. If worse comes to worse, then it has been replaced anyhow.
 
Idle mix screw is in "pipe", which is not needed. Get drimel with fiber cut off wheel and cut the pipe until you can reach screw. Nobody will see screwed up "pipe". I was cutting aluminum until I was able to cut slots in stripped screws.
103_8409.2.jpg
 
Last edited:
It looks as though Mr. Dannymax has the exact carb body I need and that we are going to be able to make a deal.
Is he making you dress in drag, stand on a table top and sing "Baby You're the Tops"?

I just want to make sure his pricing is staying the same and he's showing no favoritism.
 
ok ... now that its out ( or replaced ) what would be the right way of setting it ? how many turns out from in ? And in a previous thread it was stated that all air mix screws was set different, not the same deph/ turns ... so , what would be a good start ?
 
I forget the factory setting, but I suspect 2 turns out from the bottom would be a place to start. Do one at a time. Wasn't there a thread recently where the member did the tabulation of the # of turns to full-in, and then found they were about 1-3/4 to 2 turns out but one was 1/2 turn?
 
Yes there was . Hence the queston . Ill agree that 2 turns is a place to start !
 
In place of a sinker EDM machine, there are what they call "hole poppers" out there that are EDM type machines but use round tubing to blast through material that is conductive at a rate of 1 inch a minute. Nice toys but you would have to find a machine shop that has one. One of the uses for them is to remove broken taps.
 
Back
Top