Peer Review - New Carb Rebuild Tutorial

[mriddle]

Awesome work.

Slide nine - did you mean ".. if carb dip cannot be obtained" ?

[Matchless]

Ed,
It looks fantastic and very professional now!

I think the sentence referring to Yamaha carb cleaner maybe should have "where" instead of "with".

The O-ring sizes have always been an issue. The OEM O-rings are mostly standard metric sizes, mostly given in full or 1/2 millimeters. Many people have converted or even measured those in imperial. Later some converted the imperial measurements back to metric, thus landing up with a non-standard size.
Maybe some of the members can help provide the proper OEM metric sizes for you to show all the proper sizes in metric. That #10 size shown for example is meaningless to me, but maybe more understandable out your way.

Great work, this is going to be another jewel for the GSR collection. Your valuable experience and attention to detail is very obvious!

[Nessism]

Ed,
It looks fantastic and very professional now!

I think the sentence referring to Yamaha carb cleaner maybe should have "where" instead of "with".

The O-ring sizes have always been an issue. The OEM O-rings are mostly standard metric sizes, mostly given in full or 1/2 millimeters. Many people have converted or even measured those in imperial. Later some converted the imperial measurements back to metric, thus landing up with a non-standard size.
Maybe some of the members can help provide the proper OEM metric sizes for you to show all the proper sizes in metric. That #10 size shown for example is meaningless to me, but maybe more understandable out your way.

Great work, this is going to be another jewel for the GSR collection. Your valuable experience and attention to detail is very obvious!

Andre,

I've spent a LOT of time studying the necessary O-ring sizes and trying to match them up with available parts. The pilot screw and choke plunger cap O-rings in particular have alluded me.

Your listed recommendation for the pilot screw O-ring is a standard part but different from the Mikuni part. I've very carefully measured the OE parts at 1mm x 2.7 as near as I can tell, only I can't find that size here in the states. On the Sudco web site (US Mikuni distributor) they list the size as 1.13 x 2.7, so I think that is the official size. I'm going to order some of your recommended size and see how they work out.

The most common O-ring sizing here in the US is defined by AS568A - dash numbers. You can find these sizes very easily here. I'll cross reference that -10 size in metric for you guys that don't live in North America.

The choke plunger cap O-ring supplied by Robert Barr in his kits doesn't fit right - it's too fat and will pinch when the cap is tightened. Frankly, and no disrespect intended, but your size recommendation matches that of Robert's. This is another of those sizes that are hard to find here. I recommended a similar diameter as you, only thinner. I've frankly not tried these yet but I'm pretty sure they will work okay.

Lastly, I noticed that you recommend Viton O-rings, which I also recommend. Buna-N O-rings seem to work okay but long term durability concerns me. Viton O-rings are a little more expensive but worth it in my opinion.

Thanks for all your help and recommendations.

[bccap]

where can I download the last update ?
thanx

[SVSooke]

He updates the OP link.

[Matchless]

Ed,
I have bought quite a few 2.5mm x 1mm for the pilot screws and they work perfectly. Nice and just tight enough to keep the washer and spring in place without slipping off.
I agree with the choke o-rings, that size is just too thick and we do need something thinner. In actual fact I have not really tried to find a thinner metric stock yet. The fuel tube o-rings also need to be tight and very slightly stretched in the groove, thus slightly smaller than the groove.
I agree the best is for you to try any out before you post sizes as you said.

You have spent a lot of time on this pictorial while many people hate putting pen to paper. I think I can safely say that I speak for all of us on the forum if I say that we are very grateful for your submission and its going to get a lot of references - "Have you read Ed's document? See here: xxxxx etc."

I hope I am not frustrating you with all the suggestions, but this is also going to help us "older" hands as well.

Keep well.

[Nessism]

Ed,
I have bought quite a few 2.5mm x 1mm for the pilot screws and they work perfectly. Nice and just tight enough to keep the washer and spring in place without slipping off.
I agree with the choke o-rings, that size is just too thick and we do need something thinner. In actual fact I have not really tried to find a thinner metric stock yet. The fuel tube o-rings also need to be tight and very slightly stretched in the groove, thus slightly smaller than the groove.
I agree the best is for you to try any out before you post sizes as you said.

You have spent a lot of time on this pictorial while many people hate putting pen to paper. I think I can safely say that I speak for all of us on the forum if I say that we are very grateful for your submission and its going to get a lot of references - "Have you read Ed's document? See here: xxxxx etc."

I hope I am not frustrating you with all the suggestions, but this is also going to help us "older" hands as well.

Keep well.

Andre,

I appreciate the suggestions. Actually, I need to read back though this thread and make sure I haven't missed any. There have been a couple I've dismissed as being "out of scope" and the like, but overall I think the suggestions have made a huge improvement to the original document.

[robertbarr]

Let's see:

Nice big type, for those of us wearing tri-focals and worse.

Good, well-lit photography.

Anyone following the instructions starting on p. 48 is bound to get a faceful of cleaning spray or compressed air, so I'd suggest eye protection at that point. Of course, you could add 85 pages of safety warnings and not cover everything, but this is one time when the risk to vision is really high. Maybe drop a pair of goggles in your tools list.

I like the suggestion to re-use existing jets. That's fine for carbs that haven't been tinkered with. For those that have, maybe a reference to original jet sizes might come in handy, so while the carbs are conveniently apart, the user can know where to look to find the numbers for the parts he has, to compare with OEM.

You call for a "-10 size" O-ring for the fuel tubes, which is fine, but the word 'dash' and/or AS568 would help a search engine zero in on the right item. Not many people understand that a 'Dash Size' is the according-to-Hoyle term that parts counter folks and/or suppliers (McMaster-Carr) would understand.

It's pretty evident that a lot of thought went into this one. Nice job.

I counted six photos (prior to disassembly) that include the clutch cable guide, each from a different vantage point. That should come in really handy for the half-million people who forget how that was originally positioned.

[Mekanix]

What about removing the butterfly valve and assembly, there are two seal's and plastic washers that could be affected by the dip.

By removing the aluminum end cap and the E-clip under that, the whole assembly can be removed along with the seals.

[Dogma]

Nobody around here ever does that, and nobody has ever reported a problem with them in the dip. I've also never heard of these seals failing.

Do you remove the plate from the shaft? If so, how do you secure the scews to make sure they can't come loose again. Do you swage them again?

[Mekanix]

Do you remove the plate from the shaft? If so, how do you secure the scews to make sure they can't come loose again. Do you swage them again?

I remove the plate and shaft along with the seals and plastic washers.
The screws hold tight after reinstalling. I've never had one back off but I acknowledge it is still a risk.

Nobody around here ever does that, and nobody has ever reported a problem with them in the dip. I've also never heard of these seals failing.

I've never dipped with them installed so I can't say if it has any effect.
And I've also never herd of anyone having problems with them.

However I have seen one set of carbs with fuel residue coming from those locations.



I have to say though that If I were a noob and saw this tutorial for the first time, that I most definitely could do the job and be confident in it.

Great job Ed

[Dogma]

Is it possible to remove the seals and washers without removing the plate from the shaft?

[5azzmonkey]

Great job! Thanks for taking the time to put this together.

[Nessism]

Is it possible to remove the seals and washers without removing the plate from the shaft?

The butterfly needs to be removed. I've done it before but it's very easy to strip the screws since they are locked to the shaft and if you press the screwdriver tip really hard into the screw the shaft could get bent. Based on the routinely positive feedback from people that dip their carbs with the seals intact, I don't think there is significant risk in doing to.

[saltcitytattoo]

is there a size for screws in the bowl, cap, and two bars that hold them together so we can change them out to allen heads?