1990 Radian ugh.

As the title states i just got myself a 1990 Yamaha Radian. And i must say, this little bike is awesome! So i bought this beauty from the original owner with only 3686 miles on the bike. But there are a few things I’ve noticed with this bike. For one there are POD filters on it. Not my cup of tea due to well from my understanding it’s really a nightmare with these carbs. Two is this damn rattling i get whn the bike hits about 3k rpms sounds like chain slap / cam chain. And three is finding parts. I know i know i did this to myself but this bike is clean and really a fun little bike to ride when it wants to play nice. Ive had issues with the carb it runs rich and lags while taking off at low rpms then rides fine. I was told there is a jet kit due to poding the bike but i cannot for the life of me find a stock airbox for this thing. I have put new plugs n wires on this bike re-did (ALL) wiring thanks to my dad properly because id in his words muck it up and liok like a jackass as my bike catches fire. Let alone finding anyone willing to work on this bike. So in turn makes me the man for the job any i mean any help i could get about this bike id appreciate. I had a 92 Seca 2 and loved that damn little bike but this things temperamental as all hell. Ive changed the cluch the oil wires hoses breaks tires you name it the last is this carb and god is it a pain in the ass. Could use any type of info you believe i need or any way to point me in the direction of parts. Thank you!

 

Really nice machine, great find. Are your header pipes tight to the head, or rattling baffles in exhaust. Should not be an engine problem at that miniscule mileage. Len aka Chacal sells most of the parts for the XJ series of motorcycles contact him at info@xj4ever and look on the restoration parts, supplies at the top right of your screen to find out if he has parts for the Radian. Most of the time with running issues the carburettors are the problem due to the age of the bikes and they have probably never been removed because of the mileage. Plenty of help here. I don't know how many owners get the bikes running well with pods, but you are better with the standard factory setup if you can find the parts from what I have read.

 

Thanks brother no i thought the same thing about header pipes but nope sounds like the top end which from my memory is where the cam chain would be is basically right up against that plate so unfortunately, I might have to take that plate off so that way I can see what actually is going on see if there’s any kind of metal shavings or whatever in the motor. But the last time I drained the oil and changed it, which was quite literally two weeks ago. There was absolutely no metal shavings ran through with a magnet, couldn’t find anything.

 

I wouldn't expect any motor damage if that's the mileage.

 

Very clean bike!
I have that same rattle in my 1987 radian yx600 (60k miles). I also have a 1986 (20k miles) that runs but isn’t roadworthy.

I’ve changed the oil in mine several times and haven’t found any shavings. I’ve adjusted the valves, cam chain tensioner, etc..

I’ve decided to just live with the noise for now. I’m not ruling out an issue, but these bikes do have a unique sound to them.

Moving on:
I’d recommend j8-4cp7 Mikuni needles in all four carbs.

Also make sure you get factory style boots on the air intake side of your carbs with your filter pods.
They’ll smooth out the airflow, and if you find an OEM airbox you’ll need them anyhow.

Getting the carbs set up properly is 90% the work with these bikes. I had to go though the carb rack a few times and read quite a bit before I understood what was what. I had no previous carb experience. Replacing my jet needle, pilot jets, fuel jets, nozzle jets and fuel needles/seats with OEM parts and all
Carb o rings and fuel Tee with quality aftermarket - this was key to getting the bike running properly. Expect to pay around +\- $500 in parts for the carbs. If you cheap out on low quality aftermarket (which I’ve done) you’ll just find yourself rebuilding the carbs again after the bike doesn’t run properly.

Regarding parts:
1) Xj4ever Len Chacal can get ANY part that you need.
2) Motolab Derek is an expert on the yx600’s.