SuzukiSavage.com - Mikuni Carburetors

spacepirates

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Igni Ferroque

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Mikuni Carburetors
11/01/11 at 08:42:23

Bad news first: i was adjusting the brass idle mixture screw last night when i stripped the head pretty much flat. I was drilling a hole in it for a screw extractor when I snapped the drill bit off in the screw. well, that didn't go so well.

But wait! it was a stock carb anyways! perfect opportunity to upgrade! right?

so in my anger and desperation, i turned to ebay, mighty king of cheap used parts.

I ask-eth and it giveth: http://www.ebay.com/itm/150684423652?item=150684423652&viewitem=&sspagename=A...

is this even remotely close to what I need? It looks similar to a mikuni VM 38 (which is used not infrequently as an upgrade carb here on the forums) but i'm not positive that is what it is.

Pricing the replacement jets/slides/whatnot as per Lancer's tuning guidelines (found via the tech section) put it at around $110 just for the internal little brass bits :'( but all in all, $130 for a better carb isn't that much.

so... was this carb buy a good idea? or did I just buy a worthless piece of aluminum? AND, even if it IS something I could use, what am I getting myself into?

also, sidenote: assuming this replacement carb works out, if there is anyone out there that wants a stock carb (and a few extra jets!) and doesn't mind having to clean up my mess, let me know.

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Serowbot

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OK.... so what's the
speed of dark?

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Re: Mikuni Carburetors
Reply #1 - 11/01/11 at 09:34:42

Quote:

...AND, even if it IS something I could use, what am I getting myself into?

If you have to ask,... you're in way too deep...
Now,.. instead of just jetting,.. you're into fitment, cabling, etc...
PS,.. that looks like a mechanical slide... no room for routing that top mount cable...

I'd resell it, if you already bought it... and find a used BS40 replacement...

PS... if you can identify the carb and what it came off of,.. you'll get more for it...

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Ludicrous Speed !... ... Huh

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Grand Strand Junior Member Offline SuzukiSavage.com Rocks! Posts: 71	Re: Mikuni Carburetors Reply #2 - 11/01/11 at 18:35:08 PM sent and not sure if it went through. More Error messages :'(
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LANCER

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Savage Beast
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Re: Mikuni Carburetors
Reply #3 - 11/02/11 at 22:23:42

A lot of the used Mikuni round slides on bay are O L D. units left over from dirt racers 20-30 years back and are in pitiful shape. I have bought them in the past and ended up scraping about 8 out of 10 of them because they were not usable.
36 & 38mm new units retail in the $130-150 range.
They do require a new rubber mounting flange to bolt up to the head and a custom made throttle cable is needed if you want a trouble free throttle hookup.
You will also need an assortment of jets for tuning the new carb to your engine and exhaust setup, and a Mikuni VM carb manual is really freaking
handy unless you already know all about the round slides.
I've spent a few years doing this and know what is required.

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spacepirates

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Igni Ferroque

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Re: Mikuni Carburetors
Reply #4 - 11/03/11 at 10:16:30

LANCER wrote on 11/02/11 at 22:23:42:

A lot of the used Mikuni round slides on bay are O L D. units left over from dirt racers 20-30 years back and are in pitiful shape. I have bought them in the past and ended up scraping about 8 out of 10 of them because they were not usable.
36 & 38mm new units retail in the $130-150 range.
They do require a new rubber mounting flange to bolt up to the head and a custom made throttle cable is needed if you want a trouble free throttle hookup.
You will also need an assortment of jets for tuning the new carb to your engine and exhaust setup, and a Mikuni VM carb manual is really freaking
handy unless you already know all about the round slides.
I've spent a few years doing this and know what is required.

Yeah, I'm not deluding myself into thinking this carb is going to be in spectacular shape, but i'm just hoping it'll work given a little time and effort.

I've read your carb tuning tips in the tech section (fantastic write up, by the way!) on starting points with vm36 and 38 carbs. I figured that if I'm going to have to buy a new carb anyways, might as well upgrade while I'm "forced" to get a new carb so that i can get some benefit out of the whole predicament.

Nichcycle.com is where i've been looking at for carb parts (mounting flange, jets, and all the rest, right there!) . The throttle cable I'm not sure about, but initially i'll be happy for a "just works" kind of set up. over the winter I can tinker and source where to get the finishing touch parts.

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LANCER

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Re: Mikuni Carburetors
Reply #5 - 11/03/11 at 13:35:21

I've got the parts; flange, jets and custom cables, but won't be back home till mid Dec.
Suzuki has used 3 different types of throttle cable hookups on the LS650. One for the 80's models, one for the 95-04 models and one for the 05-present models.
I had all 3 worked up under special part numbers with my supplier.
I'm traveling and won't be back home till mid Dec though.
If you get it worked out before then, great, but if not then catch me then and I will take care of it.

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spacepirates

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Igni Ferroque

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Re: Mikuni Carburetors
Reply #6 - 11/03/11 at 20:47:13

LANCER wrote on 11/03/11 at 13:35:21:

I've got the parts; flange, jets and custom cables, but won't be back home till mid Dec.
Suzuki has used 3 different types of throttle cable hookups on the LS650. One for the 80's models, one for the 95-04 models and one for the 05-present models.
I had all 3 worked up under special part numbers with my supplier.
I'm traveling and won't be back home till mid Dec though.
If you get it worked out before then, great, but if not then catch me then and I will take care of it.

Ha, till then I've got a 1978 XS750 to tune and get ready for inspection and I just picked up a 1985 Honda Sabre to get road worthy again. I think i'll be able to wait if it means getting good parts.

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SuperSavage Senior Member Offline SuzukiSavage.com Rocks! Posts: 341	Re: Mikuni Carburetors Reply #7 - 11/03/11 at 23:11:24 Why don't you just let Lancer build one for you and be done with it?
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spacepirates Serious Thumper Offline Igni Ferroque Posts: 515 Pittsburgh, PA Gender:	Re: Mikuni Carburetors Reply #8 - 11/04/11 at 06:41:02 SuperSavage wrote on 11/03/11 at 23:11:24: Why don't you just let Lancer build one for you and be done with it? 1) money 2) pride
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Grand Strand Junior Member Offline SuzukiSavage.com Rocks! Posts: 71	Re: Mikuni Carburetors Reply #9 - 11/04/11 at 16:30:12 spacepirates wrote on 11/04/11 at 06:41:02: SuperSavage wrote on 11/03/11 at 23:11:24: Why don't you just let Lancer build one for you and be done with it? 1) money 2) pride 1) +1 2) +1 er +2 oh well yeah me too!
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LANCER Serious Thumper Alliance Member Offline Savage Beast Performance Parts Posts: 10671 Oklahoma Gender:	Re: Mikuni Carburetors Reply #10 - 11/04/11 at 17:02:30 New rubber flange for a 36/38 VM carb and custom cable +shp is $90 Pilot and main jets are $4 each; 2 pilots and about 4 main jets would be the minimum to cover variations in intake/exhaust/location.
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spacepirates

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Igni Ferroque

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Re: Mikuni Carburetors
Reply #11 - 11/05/11 at 11:26:15

got the carb in the mail today, looks to be in pretty good shape though it is missing the needle (and retaining plate).

It also has a different throttle cable "mount" that has got me confused as all get out. going back to that single ebay pic, you can just barely make out a small piece of angled metal tubing out the top of the carb. Now, I don't have a needle or any of the parts that go in the slide/piston valve, but i'm guessing the throttle cable attaches to something inside that slide through that top tube? Most vm38s I've seen have a different top cable mount.

Also found this cable on amazon:
http://www.amazon.com/Parts-Unlimited-Universal-Throttle-Cable/dp/B0022ZZF60/...
Might be able to rig it up to work with the savage's controls

And this flange (also on amazon, but nichecycles has one too):
http://www.amazon.com/Mikuni-Rubber-Flange-Typical-I-VM38-200/dp/B000GZK76Q/r...

I haven't measured the stock flange's distance stud to stud. Hope they are similar...

So, yeah. While LANCER could supply everything I need, it looks to be a touch more expensive, assuming these parts work which certainly isn't guaranteed. More research and perhaps some "leap of faith" purchases are in the future....

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spacepirates

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Igni Ferroque

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Re: Mikuni Carburetors
Reply #12 - 11/05/11 at 11:29:02

Grand Strand wrote on 11/04/11 at 16:30:12:

1) +1

2) +1 er +2 oh well yeah me too! Grin

Yeah, I know buying guaranteed to fit/work parts is easier and probably the way to go here, but it is a lot more satisfying (and cheaper if you don't screw things up) to do it on my own. I learn a lot more that way too.

by the way, found a vm "super tuning manual":
http://www.mikuni.com/pdf/vmmanual.pdf

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LANCER Serious Thumper Alliance Member Offline Savage Beast Performance Parts Posts: 10671 Oklahoma Gender:	Re: Mikuni Carburetors Reply #13 - 11/06/11 at 19:57:25 That carb manual has good info in it and it's been all over the net for years. It's not extensive as the Mikuni Manual but it's still good to have. I've had a copy for a long time Good luck with the carb work. It's been a while since I had to order a needle but I think they were around $22 (wild guess)
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spacepirates

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Igni Ferroque

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Re: Mikuni Carburetors
Reply #14 - 11/07/11 at 08:21:02

Close, $17 before shipping here:
http://www.motorcyclecarbs.com/_C62.cfm (by the way, this site has a nice break down by manufacturer part numbers which makes it super easy to get exactly what you want)

but only $6 before shipping here:
http://www.nichecycle.com/ProductDesc.aspx?code=6DP01&type=0&eq=&desc=JET-NEE...

With all the parts and some spare jets the total adds up quickly. I'll put the order in later today and hopefully by early next week I'll have a nice little project to work on.

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