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Discussion Starter #1
Alright,

I'll start off by saying that the ZR7 modifications are complete. Everything is functionnal, put new carbs in the bike to replace the troublesome old carbs that were repaired without much knowledge it seems by a previous owner.

I cleaned every orifice in the new carbs, they are speckling clean and air was blown thru jets and body passages, every oring is clean and fresh, slides go up and down flawlessly, float level was checked with a caliper and they are all within spec, the float needles don't have a ring in the rubber part due to wear, the little button on them press in and out normally, jets are stock and the correct size as stamped on them, diaphragms are without punctures and ripples

Now, for the issue:

I put new NGK DR9EA plugs in (gapped and all).

The bike runs real harsh while warming up. It feels like an intake leak, The boots from carb to cylinder head were cracked on the outside, I pulled them out and they weren
't cracked all the way through but I sealed the cracks anyway just to be diligent.

I suspected a leak from the airbox to carb boots so I used zip-ties to keep the closed along sith the spring (one beside the other) but to no avail.

I am now suspecting an exhaust manifold leak as I had removed the header before to sandblast the manifold seal collars. I sanded then on the sealing side a bit to have a nice flat surface to press against the copper donut seals.

When warmed up, the bike sounds ok, It might need a carb sync and valve adjustment, revs hang and very slowly go back to idle and are a bit sporadic at idle (maybe 100 to 200 rpms up and down).

When checking the plugs with pilot screw at 1 3/4 turns out, the #2 and #3 cylinders look very lean and the #1 and #4 were a tad rich.

Spark plug caps are brand new NGK caps with the correct OHM resistance.

It ran fine last summer aside from hard cold and slightly warm starting issues.

A Alpha moto carb sync gauge kit and new collars and manifold seals are on the way.

Is there anything I could have overlooked? I'm truly out of ideas. I don't have a huge working space as I live in a small appartment in town with inside parking but I can get away with some oil spills and mechanical work.

Riding season is starting and I'd like not to spend it hunting down gremlins :cry:
 
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