Recent posts

#1

Turning Wrenches / Carb/choke question

Last post by RDDave - Today at 09:57:05 AM

I am STILL struggling with the left cylinder on my stock RD350b. It runs a good 30* cooler than the right and fouls plugs. I have swapped most of the ignition components left to right. Both cylinders have about 95# compression. I have had the carbs apart repeatedly and reset the floats, swapped floats, etc. Changed the left exhaust pipe. Iridium plugs really helped and I can clean them and bring them back to life.

My question is about the choke. I capped off the transfer tube and the right cylinder plug is clearly lighter making me thing it was getting too much fuel, too. The needles are all the way down and the mixture screws are out about 2 1/2 turns. The bike starts first kick and runs real good until it fouls the plug.

I have the left carb apart (again) including the choke assembly. I do not see anything wrong with the rubber at the end of the plunger. No nicks or cuts or deformation. But I would like to block it just to see if it makes a difference. The thing is; I don't know of a good, reversible way to block it. And, if needed, how do you service that plunger? Is the rubber removable and serviceable? Doesn't look like it.

Any thoughts on this would be GREATLY appreciated.

#2

Turning Wrenches / Re: Discolored piston

Last post by 1976RD400C - Today at 05:54:56 AM

Did the spark plugs and combustion chambers look the same? Coolant in the combustion chamber will clean the carbon out but if the coolant was coming out the top of the dome insert that's not in the combustion chamber.

#3

Turning Wrenches / Re: Discolored piston

Last post by m in sc - May 26, 2024, 04:37:24 PM

weird they are not the same. but i wouldn't sweat it. is the RH crank seal fresh-ish?

#4

Turning Wrenches / Re: Discolored piston

Last post by RDnuTZ - May 26, 2024, 04:28:15 PM

IMO, that tiny amount of carbon only 8 miles into breaking in a new motor is normal. And only on the right side- unless you cleaned the left before the picture? Did you do heat cycles before starting to ride it to get 8 miles? On the coolant thing, you actually saw the leak and pretty confident you know what caused it and didn't enter cylinder, I don't know a simple way to look down past the pistons into the crank area to be 100% none want down inside- so you need to use your judgement how much risk you think there is buttoning it back up with the leak fixed. Others may give you better advice than me to work with.

I sold my RZ years ago but remember I had a coolant leak once too... and the way I found it was I came out to the garage 1 day and saw a puddle of vanilla milkshake under the bike. Turned out the impeller shaft seal went bad and let coolant leak into the clutch case and eventually overflowed it out the case overflow tube. You might just want to pull your dipstick and look for foam and also look in the radiator for foam to make sure coolant didn't leak somewhere else besides what you already confirmed?

#5

Turning Wrenches / Discolored piston

Last post by Aloha808 - May 26, 2024, 02:47:40 PM

Well, l removed the head to my rz to fix a coolant leak coming from the top of the dome insert.  It only has 8 miles on the motor.  The bike ran well but I discovered the coolant leak. 

Picture of the two piston are below.  There was no evidence that the coolant was entering into the cylinder.


I was wondering how concerned I need to be?  Any thoughts?

Thanks

#6

General Chatter / Re: Airtech Streamlining Closi...

Last post by The Red Scourge - May 26, 2024, 02:10:13 PM

That is truly very bad news.
They had molds for damn near anything you could ask for...all thrown away...freakin heart breaking.
 

Yeah, I'm legitimately sad about it.

#7

General Chatter / Re: Fuel line question

Last post by rodneya - May 26, 2024, 01:43:49 PM

The pink color lines I use start going slightly hard after a few years, but I use fuel line quick connects from ebay to make taking the tank off easier. They are a bit bulky and do spill whatever fuel is in the line when disconnected but I have not had any problems with them in over 4 years

#8

General Chatter / Re: Cicada's

Last post by rodneya - May 26, 2024, 01:37:55 PM

Be grateful they only emerge every 17 years or whatever it is in your area. The ones in Africa are out every year and are the loudest insects in the world.

#9

Haus of Projects / Re: Yamaha YA-1 Resurrection

Last post by RDnuTZ - May 26, 2024, 11:47:10 AM

Thanks for the link - sadly there many similar sites that never come up thanks to the commercialization and monetization of Google; I have a Forum website myself, and it has yet to show in direct searches on Google using the name of the site - I've recently moved to using DuckDuckGo or Bing; they list my site and it does come up on page 1 in searches.

I may try a wanted ad for YA-1 stuff, but suspect that what I need is a little old and too far out there. Mainly what I need is Yamaha specific like a lever perch, ignition switch and key, rubber bits like knee-grips and peg rubbers etc.

That site gave me an idea though, I might have something right up their alley to post: my wall-size Mark Brelsford 3D poster from 1973:


Thanks again for the info and link - much appreciated!


Warren

you're welcome. That site caters to all older dirt bike stuff (1989 cutoff) and it's free to join/post and he won't sell your info.    Never hurts to put an ad up and see if any response. He does require some kind of price on 4 sale ads to limit fishing expeditions. Site doesn't get as much traffic these days, but he has a companion site of FB for those that like that. Have fun!

#10

General Chatter / Re: Fuel line question

Last post by scully - May 26, 2024, 09:27:40 AM

I went the local multi dealer shop and saw these 2 ft sections of fuel line made for Mx bikes tank vent tubes. Bought 2 for like 6$ and working great so far.