{"id":9861,"date":"2024-12-27T19:26:43","date_gmt":"2024-12-27T10:26:43","guid":{"rendered":"https:\/\/www.decoboco.info\/en\/?p=9861"},"modified":"2026-09-24T13:46:21","modified_gmt":"2026-09-24T04:46:21","slug":"light-fuel-leak-gsx-r750-gr71-carburetor-maintenance-oh-2","status":"publish","type":"post","link":"https:\/\/www.decoboco.info\/en\/20241227\/everyday-events\/light-fuel-leak-gsx-r750-gr71-carburetor-maintenance-oh-2","title":{"rendered":"Light fuel leak in action? GSX-R750 GR71 Carburetor maintenance (OH)"},"content":{"rendered":"\n
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Oh! A little drip? Gushing away~
That’s one of those things that happens with old bikes. I really wish it wouldn’t leak even a single drop. <\/p>\n\n\n\n

I’ve been swamped because I replaced my car at the end of the year like this.
Parts are hard to come by, so I want to move forward with what I can do. <\/p>\n\n\n\t\t

\n\t\t\t\t\t\t\t
\n\t\t\t\t\t\n\t\t\t\t\t\t\"\"\/\t\t\t\t\t<\/a>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t
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\n\t\t\t\t\t\n\t\t\t\t\t\tYoshimura PRO-GRESS2 multi-temp meter YOSHIMURA 419-P02-0100\t\t\t\t\t<\/a>\n\t\t\t\t<\/div>\n\n\t\t\t\t\t\t\t\t\t
\u30e8\u30b7\u30e0\u30e9(YOSHIMURA)<\/div>\n\t\t\t\t\n\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\u00a512,620\t\t\t\t\t\t\uff082026\/09\/21 02:00\u6642\u70b9 | Amazon\u8abf\u3079\uff09<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\n\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t\"\"\n\t\t\t\t\t\t\t\u53e3\u30b3\u30df\u3092\u898b\u308b<\/span>\n\t\t\t\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t
\n\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tAmazon\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tRakuten\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tYahoo!\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\"\"\n\t\t\t\t\t\u30dd\u30c1\u30c3\u30d7<\/span>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\n\n\n
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RURAL GARAGE<\/strong><\/a><\/p>\n\n\n\n

Decoboco’s sister blog about moving to the countryside. We write about garage construction, grass cutting, and our daily life. <\/a><\/p>\n<\/div><\/div>\n\n\n\n\n\n\n\n

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The intake manifold is discontinued! I’ll just replace the O-ring <\/h2>\n\n\n\n
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Back then it was fastened with some mysterious flanged + button head bolts.
Maybe they wanted to keep costs down?

It’s a nightmare to remove and install.
Well, since there’s no thread locker on it yet, it’s relatively easy.
From my experience, the worst is the GSX 1400 intake manifold
That one
uses Phillips head flat screws with thread locker, <\/strong>so
if you strip it, you really need to put in serious effort or it gets dangerous. <\/p>\n\n\n\n

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Removing bolts doesn’t require any tricks.
What you need is just the right tools.
If you have solid tools, anyone can work reliably.
Without the right tools, you need knowledge and tricks instead. <\/p>\n\n\n\n

Using a 1\/2-inch size ratchet is a good choice here because it’s easy to apply force.
Having a ratchet attached makes the work much easier.
Koken bits and holders are reasonably priced.
Since it’s tight, bits and bit holders can handle most motorcycles

*The two I use are below! <\/strong><\/p>\n\n\n\t\t

\n\t\t\t\t\t\t\t
\n\t\t\t\t\t\n\t\t\t\t\t\t\"\"\t\t\t\t\t<\/a>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t\t\n\t\t\t\t\t\tCoken 5\/16 (8mm) H plus bit, full length 32mm No. 3 100P.32-3\t\t\t\t\t<\/a>\n\t\t\t\t<\/div>\n\n\t\t\t\t\t\t\t\t\t
\u5c71\u4e0b\u5de5\u696d\u7814\u7a76\u6240<\/div>\n\t\t\t\t\n\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\u00a5589\t\t\t\t\t\t\uff082026\/09\/20 18:33\u6642\u70b9 | Amazon\u8abf\u3079\uff09<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\n\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t\"\"\n\t\t\t\t\t\t\t\u53e3\u30b3\u30df\u3092\u898b\u308b<\/span>\n\t\t\t\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t
\n\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tAmazon\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tRakuten\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tYahoo!\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\"\"\n\t\t\t\t\t\u30dd\u30c1\u30c3\u30d7<\/span>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\n\n\t\t
\n\t\t\t\t\t\t\t
\n\t\t\t\t\t\n\t\t\t\t\t\t\"\"\t\t\t\t\t<\/a>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t\t\n\t\t\t\t\t\tKoken 1\/2 (12.7 mm) SQ. Bit holder 5\/16 (8 mm) H 4138\t\t\t\t\t<\/a>\n\t\t\t\t<\/div>\n\n\t\t\t\t\t\t\t\t\t
\u5c71\u4e0b\u5de5\u696d\u7814\u7a76\u6240<\/div>\n\t\t\t\t\n\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\u00a51,247\t\t\t\t\t\t\uff082026\/09\/20 18:33\u6642\u70b9 | Amazon\u8abf\u3079\uff09<\/span>\n\t\t\t\t\t<\/div>\n\t\t\t\t\n\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t\"\"\n\t\t\t\t\t\t\t\u53e3\u30b3\u30df\u3092\u898b\u308b<\/span>\n\t\t\t\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t\t\t
\n\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tAmazon\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tRakuten\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\n\t\t\t\t\t\n\t\t\t\t\t\tYahoo!\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\"\"\n\t\t\t\t\t\u30dd\u30c1\u30c3\u30d7<\/span>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\n\n\n
\"\"<\/figure>\n\n\n\n

It’s turned brown, probably from sucking in rust all this time. <\/p>\n\n\n\n

<\/div>\n\n\n\n

Strangely, the accelerator pump nozzle is bent 100% of the time <\/h2>\n\n\n\n
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I corrected it and blasted it with baking soda to finish it. <\/p>\n\n\n\n

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You can straighten it by gently stretching it with a 2.5mm diameter rod.
It doesn’t need to be perfectly straight, so if it’s bent, go ahead and straighten it. <\/p>\n\n\n\n

The rubber plug that holds the accelerator pump nozzle had deteriorated, so I ordered a replacement in a hurry.
This part isn’t available as original equipment, so I’m using one from the TM\/RS.
<\/p>\n\n\n\n

<\/div>\n\n\n\n

When it comes to Mikuni, you can get it from JBS <\/h2>\n\n\n\n
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Recently my parts orders have been mostly from Webike,
and they don’t carry these kinds of niche parts.

We were out of stock too,
so I quickly contacted Konno at JBS and they had it in stock, so they sold it to us. <\/a><\/strong><\/p>\n\n\n\n

The part number is TM29\/14. *You need 4 of them <\/p>\n\n\n\n

<\/div>\n\n\n\n

The 1\/4 slide valve is pretty worn <\/h2>\n\n\n\n
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If you want to use the VM29 on the GSX-R750 GR71 properly,
you should definitely keep spare parts on hand.

This is a carburetor from when flat valves were just starting to appear,
and quite a bit of time has passed.
When the slide valve wears out,
it becomes heavy and doesn’t return well.
Basically it’s a consumable part,
so it won’t last forever, and it’s good to understand that and work with it. <\/p>\n\n\n\n

<\/div>\n\n\n\n

Testing generic parts while we wait for the real ones <\/h2>\n\n\n\n
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Basically, if you just use OEM parts, you can eventually reach a point where you say
“this is just how it is, can’t help it” <\/strong>and call it done.

But ideally, I want to finish it 1% better and enjoy riding it more.
Suzuki has so many discontinued parts,
but I want to do everything I can to get it right. <\/p>\n\n\n\n

<\/div>\n\n\n\n

I checked the fuel tank just to be safe and it was terrible (*\u00b4\u03c9\uff40*) <\/h2>\n\n\n\n
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