Suppossed carb rebuild

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carnut108

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Think I got ripped of from my local MC shop ( Del Amo Motorsports} Got the bike back from a supposed total carb rebuild. Bike still backfiring through the right muffler so I'm taking it back Tuesday.
They saved the parts but I do not have them in hand yet. Looking over the invoice I see minimal parts listed and suspect they did not even remove the carbs from the bike. Parts listed are 4 needle valve assembly, 4gaskets , 4 O-rings, 4 more O-rings, 4 caps, 4 more caps. This does not sound like a full rebuild. Can these parts be installed without removing the carbs. Total charge $800.
 
The only gaskets on the carbs are inside the bowl, under the jet block. Takes full removal and complete disassembly to get to those.

Everything else is some type of o-ring...
 
Thanks Rusty, that makes me feel a little better. Still don't know why it would be backfiring through the muffler after a rebuild and sync.
 
Full rebuild to me would be complete removal and disassembly of carbs into their component parts and everything ultrasonically tanked. THEN and only then could I determine what needs replacement eg, coasting enrichers, needles or seats, emulsion tubes. I absolutely minimum replace everything not metal meaning all gaskets, rubber plugs, o-rings only exception might be diaphragms, choke plunger domes and enricher diaphragm.
All passageways should be shot gunned or Peashot just to ensure open passages. No better time than now to do this but it will cost at least one can of spray cleaner, maybe two.
Full reassembly with dry and wet float setting and honestly, a shop should do a CO analyzed tune after a good sync job. That $800 bucks worth to me and why a "Dealer" can say he charges the most, because he knows and does the most.
We know that ain't true right DannyMax?
In the end I hope it all works out but this leads me to suggest you score Damon Ferriaolo's carb rebuild video. Indispensible tool and information.
 
Full rebuild to me would be complete removal and disassembly of carbs into their component parts and everything ultrasonically tanked. THEN and only then could I determine what needs replacement eg, coasting enrichers, needles or seats, emulsion tubes. I absolutely minimum replace everything not metal meaning all gaskets, rubber plugs, o-rings only exception might be diaphragms, choke plunger domes and enricher diaphragm.
All passageways should be shot gunned or Peashot just to ensure open passages. No better time than now to do this but it will cost at least one can of spray cleaner, maybe two.
Full reassembly with dry and wet float setting and honestly, a shop should do a CO analyzed tune after a good sync job. That $800 bucks worth to me and why a "Dealer" can say he charges the most, because he knows and does the most.
We know that ain't true right DannyMax?
In the end I hope it all works out but this leads me to suggest you score Damon Ferriaolo's carb rebuild video. Indispensible tool and information.

Unfortunately you're right Patrick!
 
Think I got ripped of from my local MC shop ( Del Amo Motorsports} Got the bike back from a supposed total carb rebuild. Bike still backfiring through the right muffler so I'm taking it back Tuesday.
They saved the parts but I do not have them in hand yet. Looking over the invoice I see minimal parts listed and suspect they did not even remove the carbs from the bike. Parts listed are 4 needle valve assembly, 4gaskets , 4 O-rings, 4 more O-rings, 4 caps, 4 more caps. This does not sound like a full rebuild. Can these parts be installed without removing the carbs. Total charge $800.

Patrick, when you get the old parts post a pic of them we can tell you how far into the carbs they got. The 8 caps sound like the rubber plugs that go in the jet blocks (4 large, 4 small) and they would pull the rack to get to them.
 
Try changing plugs recently? Just throwing it out there met a guy with a vmax had backfire prob threw E3 plugs in and it was gone. Theres up and down reviews about them Im running them with no problem not saying buy them just maybe throw new plugs in see if anything changes?

Sent from my SCH-I535 using Tapatalk 2
 
I thought the coasting enricheners were of a diaphram design, and had no gasket involved. At least, that's the way I'd describe them - diaphrams - and those are around $40.00 per carb. If the shotgun cleaning proceedure is not done correctly, or if a person sprays carb cleaner indiscriminately into each/every visible hole during the shotgun proceedure, coasting enrichener diaphrams can, and will, become damaged resulting in very bad engine idle, if the bike will start at all. (don't ask me how I know this, and I'll tell no lies)
 
I thought the coasting enricheners were of a diaphram design, and had no gasket involved. At least, that's the way I'd describe them - diaphrams - and those are around $40.00 per carb. If the shotgun cleaning proceedure is not done correctly, or if a person sprays carb cleaner indiscriminately into each/every visible hole during the shotgun proceedure, coasting enrichener diaphrams can, and will, become damaged resulting in very bad engine idle, if the bike will start at all. (don't ask me how I know this, and I'll tell no lies)

The starter enricheners (often referred to as choke assemblies) have gaskets.

Yes, the coasting enricheners are diaphragm type valves.
 
Rookie VMAX owner trying my first Carb rebuild. This is probably stupid but any suggestions about getting the needle valve assembly
out?
I’d just replace the valve piece and not the entire assembly. I make sure carb cleaner can go in and out and blow out with compressed air. Never had to replace the entire assembly.
 
There are plenty of threads you can search for on here about the carb cleaning process. One of the members has a media presentation you can order for not much more than lunch money. Compared to what shops charge for labor, it's a deal. He also has other VMax media jobs. Need to replace 2nd gear, or tear down your engine? He's got 'em. (5) Damon | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)

I agree with maleko89, rarely do the needle valve seats need replacement. You can use a dentist's mirror to check them out for wear. Maybe if you get the bike and there's no air filter in it, or it's got 50K+ miles showing. The dead giveaway it needs to be done is if your gas tank is shiny-clean (no gum, no rust, no floating debris, gas filter is clean) and a carburetor overflow tube sticking through that narrow bar linking the carbs below the CV caps is peeing fuel onto your floor. That is a very dangerous condition if you have a gas-powered water heater in your garage!

If your 'best efforts' fail you 😟😫 don't damage anything, box-up the debris and send it to dannymax at [email protected] 🤔😉👍
 
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You fix bike yourself or pay lots of money. Carbs are not the only reason for backfiring, it is usually "forward firing", not backfiring. Exhaust leak is very common reason for "forwardfiring" Old bikes usually need lots of work and for some reason mechanics don't want to work for free. I cleaned/rebuilt about 100 carbs and I still hate the stinking job... Additional problem for mechanics, sometimes they don't know which parts are needed until they take carbs apart and clean them. Then they have to order parts and wait a few days. Sometimes nothing is needed.
 
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