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double check float level. if its richer on the RH cyl, id bet its too high. (pull plugs and check them after idling)

Float level was checked and adjusted. Same condition. I then swapped the carbs left to right and the high idle followed the carb. I pulled both carbs and inspected them. The floats were set very high(low fuel level in bowl). I adjusted them and the condition remained. I did inspect the jets, and somehow the mains are Mikuni branded(square in a square logo) 138's. I believe the jet sizes are the same numerically from keihin to mikuni and they appear physically identical to the Keihins that I have. Any objections to me leaving those in there?

The pilot jets are off brand and the printing is different between the two. Turns out, 38's are the ones I dont have genuine versions of... But I think this may fix the idling issue.

Regarding the Needles, I am running the jjh. The bike seems a bit fat in the middle throttle input. Thinking of a leaner needle such as JJJ or JJK. Thoughts on this?

Off topic, but great looking bike!

Thank you brotha! Love riding this thing.

yeah., its hard to tell by a pic. how deep was that scuffing?

It was not deep, crosshatch still present under the vertical 'scuffing'. 

Hello all, I have been riding the RD400F after the restoration for aprox 150 miles. I checked the head torques after the first run and they were very very loose. Highly recommend to check this on the regular!I stuck a bore scope in the cylinders to find good burn pattern on the pistons and the jetting isnt too far off based on ridability and reading the plugs.However, there are signs of wear on the cylinders, especially above the exhaust port. I am used to plated cylinders showing very little wear after 200 hours of hard use, so this is a bit alarming. The bike sounds tight and I always warm her up before getting on the gas. Would you say this wear is normal for a non plated cylider?

Hey guys, I am finally putting some miles on to the bike and its a ripper! Love it.

I do have a question. The idle seems a bit uneven. The carbs have been synchronized and all adjustments are equal. To do this, I removed spark plugs from opposing cylinders and let the bike run on one cylinder. I adjusted the idle to allow the bike to run at 1k rpm on each cylinder, then installed both plugs and turned back the idle adjusters equally.

The left side cylinder has a stronger idle, it puff puffs seemingly every combustion stroke, while the right side will puff puff much less often(normal two stroke behavior), like once every couple seconds.

To compensate for this, it liked a half turn in on the left and screw and a half turn out on the right. The idle is much better like this. Above idle it is perfectly even. Is this indicative of an air leak on the left cylinder?

Grease for me. Unless the contact surfaces are roached. Then I go with high tack spray.

Is a little spark knock normal on these bikes? I can hear it ever so slightly at mid rpm wide open. Once the revs increase, it is not audible. I have verified timing with test light. Engine not modified at all. Pump 91 gas.

Who is Nick and how do i find him?

Mark was referring to Nick Pastore of Vintage Smoke who offers a version of the Dyna S ignition customized for the RD
https://vintagesmoke.com/product/dyna-s-ignition-for-uscanadian-rd400-and-daytona/
https://www.ebay.com/itm/195844170963

Gotcha. Thanks for the clarification.

The lightning is super clean!

Some local boys! Good stuff! Would love to go for a mines rd loop ride some time

That bike is rad. I would pump it up with a fully built set of 350 cylinders and ride that shit illegally!

save some and buy a cdi or nicks dyna. those are very hit and miss.

remember, rd250/350 igntions fit as well. r5 ignitions (aftermarket) is not specific to r5

Gotcha. Who is Nick and how do i find him?

For the same price, one could go with this treat land full kit. Recommended? https://www.treatland.tv/HPI-CDI-mini-rotor-ignition-system-yamaha-RD350-p/hpi-yamaha-rd350-mini-rotor.htm

How are these? I have read they are known to fail. $300-400 is a lot for me, this seems like a viable option at $150


https://www.ebay.com/itm/Tytronic-Electronic-Ignition-for-RD350-RD250-R5-and-DS7-UPGRADE/113182861022?hash=item1a5a3966de:g:E6UAAOSw5KRbZRUU:rk:1:pf:1


How are the optical ignition setups? Such as Crane XR700.

My bike in the past had a crank bearing cage that was letting go over time. Looked very similar to this, pecking the piston and cylinder head.

I checked the timing on my bike today. The timing originally was set to 2.2mm static. But after riding it around for 50 miles and breaking it in, the static read 1.7-1.8mm.
I set both LH and RH to 1.84MM static, set the pointer on the stator and checked with a timing light. I only have a snap on digital version which is quite old. The light would jump around quite a bit until I advanced the timing on the light 1-2 degrees, then it cleared right up. Kinda odd.

I am still trying to understand exactly what changes when the bike is running vs static, timing wise.

I heard slight detonation with the original timing of 1.7-1.8. Is some spark knock normal for these bikes?