Hello everyone, and Merry Christmas Eve! Jared here again. For my past birthday my grandpa gave me his 75 rd350, amazing birthday present! When I got it, it was running only with choke and was sitting for a few years. I got a new battery, cleaned the carbs a few times on it now, new fuel lines, filters, carbs rebuilt. Now whenever I try to start the bike it will only run if I cover the intake. Also when it is "running" its idling extremely low, Also when I am covering the intake im getting a considerable amount of gasoline on my hand. Havent synced the carbs yet because I havent been able to get the bike warmed up enough to do so. Any ideas? Again, im a newbie at all this stuff but very eager to learn!


Thanks so much!

-Jared 

I have a couple of suggestions .
You have already stated you've rebuilt the carbs . Assuming you've possibly used
an aftermarket carb kit ( Keyster ) , that might be some of your problem .
The jet brassware in the kits isn't as accurate for metering fuel as genuine
Mikuni components . The supplied needles seldom bear any resemblance to
the original needles .
Another trap with the Yamaha twins is the choke / starter jet is in the left float bowl .
If your carbs have been reassembled with the left bowl on the right body , your choke
won't work , and starting the bike will be difficult , if possible .
 

Wow, I did not know that the bowls could get mixed up, Im definitely gonna have to check that! Thanks so much

I'd forgotten about the bowl swapping, good to be reminded. & another favourite trick was people end up swapping the slides to opposite sides which means they need to be turned half a turn so the cutaway is forward causing a super rich situation which doesn't sound like yours if you need to hand choke it. But fuel on your hand if lots sounds like its not sucking like it should. Has the cylinders been off so pistons could be back to front with piston reed holes towards the exhaust. Or is there a reed valve problem, they don't need to seal but if one petal is missing or one broken on each then that'll cause grief. All unlikely stuff. Also without the air filter restriction it might be too lean for full throttle but should still try up to that point. Idling very low does have me thinking slides as goes super rich I think even at idle.

beautiful bike, good luck getting it to run, please share what you learn
I am thinking about one of these, or a triple, for next project

awesome gift! those would haul ass back in the day. also, if it sat a long time, the crank seal could be sucking air

Great bike I have one too they are wheelie king’s love the sound of the twin cylinder’s 

Pilots are still plugged and maybe the choke circuits are plugged with varnish  COMPRESSION,,FUEL,,SPARK  You appear to have 2 of these.
Doug

Can you take some close up pic of your carbs