{"id":39761,"date":"2020-04-12T15:11:46","date_gmt":"2020-04-12T06:11:46","guid":{"rendered":"https:\/\/www.decoboco.info\/en\/?p=39761"},"modified":"2026-09-24T13:45:24","modified_gmt":"2026-09-24T04:45:24","slug":"super-xr250baja-md30-carb-oh-and-light-maintenance","status":"publish","type":"post","link":"https:\/\/www.decoboco.info\/en\/20200412\/everyday-events\/super-xr250baja-md30-carb-oh-and-light-maintenance","title":{"rendered":"Super XR250 BAJA MD30 Carburettor overhaul and light maintenance"},"content":{"rendered":"
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The photo is an XLR250 BAJA I used to ride back in the day. *Not related to this work. Just feeling nostalgic~
Wow, it really screams 20th century… Back then, if you wanted to take photos easily, you’d use a Fujifilm QuickSnap.
It’s supposedly 35mm full-frame?

*We do not accept any work on motorcycles and scooters without current inspection certificates. If you have a main bike with us, we can work on a second bike. <\/p>\n\n\n\n\n\n\n\n

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This is the only muddy bike at our shop. It’s being used the right way, I think to myself.

Dusty means we just wipe it down without touching anything. Pretty easy, right? <\/a><\/p>\n\n\n\n

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I was a bit startled… Here’s what proper emulsification looks like. <\/p>\n\n\n\n

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I seem to recall… the serviceability was really bad… How do you even get it out…
You have to remove the intake manifold too and give yourself a lot of clearance. <\/p>\n\n\n\n

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As expected from Keihin and Honda, this vacuum carburettor is packed with annoying mechanisms. <\/p>\n\n\n\n

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A TPS is installed but it’s not adjusted… <\/p>\n\n\n\n

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There’s a diaphragm and valve installed. The linkage that lifts the piston is interesting too.

It’s so esoteric~ I’d really like to see the manual. <\/p>\n\n\n\n

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Since it’s a running bike, the inside was clean. <\/p>\n\n\n\n

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I cleaned just the essentials. <\/p>\n\n\n\n

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This is how the piston lift linkage works… Pretty high-tech? <\/p>\n\n\n\n

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Quick, quick, quick~ all cleaned up.

I always think about it… it really is the equipment that makes the difference… there’s no going back to the old days…
Wistfully. <\/p>\n\n\n\n

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I also applied Gun Coat to the fine details. Just a little bit really boosts the finish. <\/p>\n\n\n\n

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Rubber float valves have a long service life.

However, bikes with rusty tanks or long-term storage need replacement.

The stepped tip is something I haven’t seen much of, but
\u2022 Rust creates a wet-blasted, rough, worn surface
\u2022 The rubber tip becomes hard like plastic
\u2022 The body wears and tilts

and so on… If you’re concerned, please have it replaced. <\/p>\n\n\n\n

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The fuel level has a strong “don’t touch the whole thing” vibe… As expected from a Keihin carburettor. <\/p>\n\n\n\n

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Then we assemble and we’re done. <\/p>\n\n\n\n

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Replace the intake manifold, clamps, and hoses. <\/p>\n\n\n\n

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Spark plug… I’m glad I ordered it ahead… I’m glad it came out… <\/p>\n\n\n\n

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We cleaned the air filter and lubricated the chain, and <\/p>\n\n\n\n

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We replaced the fluid.

The engagement that was so-so before now goes tat-tat-tat~ \u266a.

What’s strange every time is that with a running carburettor with no clogs,

there’s no major problem\u2014just cleaning, checking, and reassembling brings it back to life significantly.

It’s amazing how a tiny thing can hold you back, and I learn something every time.


All done. <\/p>\n","protected":false},"excerpt":{"rendered":"

The photo is an XLR250 BAJA I used to ride back in the day. *Not related to this work. Just feeling nostalgic~ Wow, it really screams 20th century… Back then, if you wanted to take photos easily, you’d use a Fujifilm QuickSnap. It’s supposedly 35mm full-frame? *We do not accept any work on motorcycles and scooters without current inspection certificates. If you have a main bike with us, we can work on a second bike.<\/p>\n","protected":false},"author":2,"featured_media":39734,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"pochipp_cv_data":"","swell_btn_cv_data":"","footnotes":""},"categories":[1924],"tags":[230,217],"class_list":["post-39761","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-everyday-events","tag-cab-oh","tag-super-xr250"],"_links":{"self":[{"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/posts\/39761","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/comments?post=39761"}],"version-history":[{"count":0,"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/posts\/39761\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/media\/39734"}],"wp:attachment":[{"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/media?parent=39761"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/categories?post=39761"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.decoboco.info\/en\/wp-json\/wp\/v2\/tags?post=39761"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}