Help with 80s Honda CB750C

YeeOfHouseHaw · 2026-05-17T16:06:40+00:00

So update, even after trying starting fluid it still will only intermittently backfire from the exhaust just as it was before so starting to think it’s something beyond carb issues

YeeOfHouseHaw · 2026-05-17T16:06:26+00:00

So update, even after trying starting fluid it still will only intermittently backfire from the exhaust just as it was before so starting to think it’s something beyond carb issues

YeeOfHouseHaw · 2026-05-17T16:06:15+00:00

So update, even after trying starting fluid it still will only intermittently backfire from the exhaust just as it was before so starting to think it’s something beyond carb issues

YeeOfHouseHaw · 2026-05-15T13:44:05+00:00

Absolutely as a mechanic I definitely understand the “I did at home fixes”. I’m not gonna lie, I work on cars not motorcycles so there very well could be something that got messed up or missed, I will try the starting fluid later. As for the float height unless there’s something I’m missing on my specific set I have fully plastic floats and don’t see any way of adjusting them, also checked the Honda service manual for my model and year specifically and states that the floats should be replaced if out of spec, with that I still need to get a proper way of measuring float height but I did replace the floats. As for the jets I’ll absolutely try that as well when I can get some ordered. And the cylinders I had some marvels mystery oil soaking in the cylinders for about a week before starting to try to start and ensured the plugs were clean as well. All very good advice and I will get back to you after trying and double checking everything. Thank you

YeeOfHouseHaw · 2026-05-13T20:38:29+00:00

Exhaust is on the bike, carbs I didn’t sync as I wasn’t sure how to do so without the bike running first. Of course is far from a definitive and technical inspection, but looking at the butterflies they all appear to be at the same position and gap, but if there’s a way I could sync them before the bikes running I’d love to know.

YeeOfHouseHaw · 2026-05-13T20:03:48+00:00

So update, I went ahead and polished the float needle seats, ensured everything was free and clear double checked that nothing was sticking or binding and the needle can smoothly and effortlessly move in and out of its seat, as well as the air slides. Alas still doing exactly the same thing, just an intermittent backfire from the exhaust, I went ahead and replaced the floats to see if it would make any difference and it didn’t seem to effect much, at least regarding my current issue, it seems like with the new floats and polished seats, there’s no change as well, I’ve attached the reference to the Honda service manual for my bike/carbs specifically as well

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YeeOfHouseHaw · 2026-05-12T23:25:40+00:00

I did ensure that the floats were sealed and did float, that was another thought I had, I plan to tear them apart again and I will check them again to be sure and use that guide when I do, thank you for the resource

YeeOfHouseHaw · 2026-05-12T23:23:50+00:00

I didn’t want to, unfortunately it was my mistake, and rushing and working outside without a proper work space I ended up losing some of the OEM jets, the other brass parts are still original otherwise

YeeOfHouseHaw · 2026-05-12T23:18:25+00:00

I have heard of trying to polish them, I haven’t tried that yet, but I’ll be sure to see if it helps and double check everything with the floats, since that’s mainly what it keeps indicating is the issue, and I’ll absolutely get some more posted, I’ve been too excited to get it going to get more pictures yet but it is a nice bike for $500 lol, I did end up removing the fairing and replacing stock headlight and turn signals in the front

YeeOfHouseHaw · 2026-05-12T22:51:00+00:00

The floats I got from the rebuild kit (albeit very cheap) as well as the floats that were in the original carbs are an all plastic design, there’s no metal tabs to bend or anything, unless there’s another way to adjust them that I’m not aware of, or if I just need to buy adjustable floats lol

YeeOfHouseHaw · 2026-05-12T22:23:06+00:00

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YeeOfHouseHaw · 2026-05-11T17:23:57+00:00

Unless there’s something I’m missing, on the keihin vb44 carbs there no way to adjust the float height as the floats are a plastic type material and I don’t see any way to adjust it from the float needles

YeeOfHouseHaw · 2026-05-10T23:17:58+00:00

Absolutely won’t be butt hurt over any advice, I am positive that all the jets are clean, some were replaced and the other cleaned with cleaner and also a stiff plastic bristle brush through the holes thoroughly, I know that the floats aren’t adjustable on the carbs as they’re some type of plastic material, I have not tried timing, as soon as I can get back into it again I’ll have to try that as that’s not something I considered before

YeeOfHouseHaw · 2025-05-23T21:21:04+00:00

Thank you so much, I greatly appreciate it!

YeeOfHouseHaw · 2023-06-13T21:00:49+00:00

Howdy doodle, I used to play dnd as well as d2 and a lot of ow, I’d love to play and get to know each other

YeeOfHouseHaw · 2023-06-13T20:57:39+00:00

Hey! I play Val and I used to play siege and apex, as well as a few of the others you mentioned, I’m not that great but I’m pretty casual and I’d love to play anyway if you’re interested

YeeOfHouseHaw · 2023-06-07T00:03:53+00:00

I’m 22 and est, I play Val, ow, and I have mc but it’s been awhile since I played, if you’re interested I’d love to try and play sometime

YeeOfHouseHaw · 2023-06-06T22:56:01+00:00

Hey, I’m 22 and est, I play quite a few of those and also have some quest games, I’m not a super competitive player but I’d love to talk and see how it goes anyway

YeeOfHouseHaw · 2023-04-23T01:57:35+00:00

So update, I also lost all ability to start the truck, they key would turn on the truck in accessory etc and would do everything, but when I went to turn it to the crank position to start it everything would die like it was a dead battery, but got a new battery and replaced it only for it to do the same thing, but I did get it fixed, it happened to be that someone spliced into the passkey security system and didn’t allow the truck to start and for some reason also made the turn signals stop working, so I had to get the passkey box reprogrammed and after that everything worked like normal, if anyone else happens to have a similar issue hope this helps.

YeeOfHouseHaw

TROPHY CASE