Daytona

[cygnus]

Hey all.    I've pretty much given up working on other peoples bikes unless its interesting. One owner bike just over 5000mi which was parked in '91. It has some warts but is a really decent example. Gentleman is in his late 60's, he and the mrs want to get her in the breeze to put a few miles on for nostalgia sake before selling it. Not a build per se but its a fair trade to show pics in return for a little "tribal" knowledge. He is on a tight budget so I thought I would hop in to ask things which could alleviate me making "bad" purchase decision on repop items etc. I'm quite handy but haven't spun a wrench on an RD in a couple decades.

[cygnus]

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[cygnus]

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[cygnus]

You can imagine what this smells like hahaha. I believe he has a repop gas cap in his future but I'll throw it in a bucket of evaporust for a couple weeks and see what comes out. It was non ethanol fuel with stabil but he learned the hard way about walking by it for decades and ignoring it. Obviously there will be some rust but the significant portion of this is "scale" from the fuel and stabil evaporating....you can see where I poked it a little to root around. i've gotten pretty adept at cleaning these things and saving the paint over the years. Its just damn time consuming and not "fun" work

[cygnus]

And then he gets lesson 2 in walking by for decades

[cygnus]

At least he got the satisfaction of seeing the bastard dead 

[cygnus]

Little turd actually chewed one of the flow diverters off to make his corn trips up the snorkel easier. As these box parts are unobtanium and priced accordingly when found I think I will just cut the other one off so its "even" flow as in the grand scheme of things it likely doesnt matter. Or if I have time I may try to fab something to put it back.

[cygnus]

Looks like he spit all the diverter/filter shavings through the cage.

[cygnus]

So, my first question is regarding the intake manifolds. These are hard and cracked, not cracked through yet but won't be long. I see they are available repop but only find two choices for the oem carbs. One set has no stuffers and no vac ports. The other style has the stuffers but large ports/barbs for a crossover hose. Does anyone make a manifold for the Daytona type that has the small ports/barbs for the exhaust valve /check valve tubing?

[SoCal250]

So, my first question is regarding the intake manifolds. These are hard and cracked, not cracked through yet but won't be long. I see they are available repop but only find two choices for the oem carbs. One set has no stuffers and no vac ports. The other style has the stuffers but large ports/barbs for a crossover hose. Does anyone make a manifold for the Daytona type that has the small ports/barbs for the exhaust valve /check valve tubing?

Welcome. Nice looking bike!

Here's a method for returning rubber to pliable and soft again. This of course is for parts that aren't cracked. Before hunting around for parts and spending money on repop rubber bits I would first attempt to retore the original pieces. 

I don't believe there are repro 2V0 manifolds available. Only the regular 1A1 RD400 type and the RZ/Banshee type.

[Organicjedi]

Do you mean an intake boot that has the openings to use a crossover tube but does not have the protrusions on the back? If that's what you're asking then yes. I bought a set of UPP manifolds for a Banshee for my 400. Those did not have the extra plastic protrusions to cut off on the cylinder side.

You can get ones that have those protrusions, you just need to cut them off. I went with UPP because I was hoping they'd be more durable than the Yamaha ones I had. Those lasted me two seasons before cracking.

[SoCal250]

I believe he is referring to the 2V0 manifolds that are unique to the Daytona. They have metal inserts for connecting a rubber hose instead of the larger ports that are found on the RZ/Banshee manifolds.

[cygnus]

Thanks guys. Yeah, those are the ones. I have rejuvenated manifolds before but since these are cracked I wanted to replace them if possible. The cracks aren't all the way through yet but I don't want to take a chance on a sudden air leak when they decide to. The exhaust valve system seems to function properly using a mity vac and I want to leave it as "original" as possible per his wishes.

[SoCal250]

I want to leave it as "original" as possible per his wishes.

Makes perfect sense. There aren't many original ones left.

There is a set of manifilds on Ebay right now. No telling if they are better than the ones you have now.
https://www.ebay.com/itm/1979-Yamaha-RD400-Daytona-Special-RD-400-RD-400-RD400F-1887-REED-VALVE-INTAKES/233209670080

[Tuck]

Looks like a nice survivor. I have a bad feeling about the inside of that tank, you might need to replace it. Clean Daytona tanks are hard to find. There's one on CL in my area that looks decent. Let me know if you want the link. Let the fun begin!