Carburetor Surprise - Screwed?

I recently bought a 00' DR-Z400E the other day. When I went to pick it up, it was having a problem idling, but was fine once it warmed up. Started no problem on full choke. Struggled with the choke was off until it was running for a while. I figured it was the pilot jet, no big deal. Pop open the carb and find a jet well with a chunk out of it and a plastic tube wedged in to fill the gap . The plastic piece was wedged in there fully, and was actually functioning, but it chokes down the tube quite a bit. So I found my idle problem... I know I cant JB weld this since it will be soaked in gas or I would use the plastic as a mold and build up around it. Could this be welded? Should I just bore out the plastic piece that has been working for a little more throat? I really don't have the money to buy another carb right now. The Keihin carbs on ebay are hovering around $400 :( and I haven't been able to source any cheaper used ones. This is my first post, and I haven't seen a BST/FS section anywhere on TT. Any suggestions for possible repair or cheaper replacement? I'm so irritated since the seller lied to my face about the condition of the carb when I specifically asked!

Here is the busted well


Aaaand here was the previous owner's fix


Edited by S_Mitch

There exist fortified epoxies similar to JB-Weld that tolerate exposure to gasoline. Weicon Reipair Stick Aqua is one example. Here's the data sheet on the stuff - they expressly say that it's for patching fuel tanks: ... however, this particular compound doesn't resist ethanol so if you only have access to fuel with ethanol I'd look further. I'm pretty sure you can find something.

I would be more inclined to drive in a short piece of thin walled copper or steel tubing. Look at the auto parts stores for a drive in vacuum fitting or hose coupler.

Replace your carb with an fcr :)

I have one with the exact same deal, minus the plastic piece wedged into it. It takes a while to warm up and idle well, but once it is warm it is fine. I have cleaned the carb multiple times and messed with it until I'm tired of doing so, I just ride it as is. It runs just as good as my other one once warm, but just take a while to warm up so I genearlly just run it a little with the choke on and/or turn up the idle until it is warm and then turn it back down once it is warm enough to idle slower.

Basically as long as I'm riding it and in the gas it's fine even when cold, once warm it's fine regardless so I just ride it. Not spending the $$$ on another FCR carb when this one runs fine with just a little effort when cold.

Edited by dirtdude723

It's already an FCR... and this is why I am sad. I'm starting to lean towards the tubing idea. Also noticed that the buffer plate (1157-812-754) is missing. I'm assuming he took it off because it wouldn't fit with his rigged plastic.

I doubt the damage is hurting anything. The old repair is just fine if not actually pointless. I see a dirty carb that needs better cleaning. (fuel gum). I see some damaged jets (from rough handling and wrong tools). Replace the pilot jet with a new one (#45) and evaluate if it makes any difference.

Just bought a super clean 2004 DRZ 400E that had sat so long that the owner (had a lot of money but no time to ride) had taken it a couple of YEARS ago to the dealer just to have the carb cleaned. It had really bad carb issues but was basically a new bike. The point being I had the carb apart 3 times in a week. SO . . . . There is a small jet up in there but the split in the metal (how in the HE>>> did he do that!? ) should make no difference. After finally getting all the corrosion from the brass parts (never saw that before it was flakes of brass) out of the float bowl and jet passages (but no dirt at all) the bike still didn't caburate properly - turned out the almost never used accelerator pump diaphragm had started to delaminate. The neoprene was delaminating from the woven substrate. Replaced that and it ran great. Your carb (thanks for the pix) looks like it has been around long enough that you might want to check that (its on the bottom) . There is also a diaphragm in the "coast enrichner" on the side of the carb. they are NOT the same - I know because of long round trip and reorder when the parts guy ordered the wrong one. Also you can remove the octopus coast enrichner and put some rubber caps from auto supply over the various fittings that the hoses go to. I read this somewhere, it works fine, it made feel like a real mechanic and I have no idea whether it helped because i couldn't ride the bike with with the carb screwed up anyway but the carb sure looks cleaner. Also you can can the plastic cover over the throttle pully if you aren't in a lot of dirt (which might plug it up anyway). If you "T" the crankcase ventilation hoses together you can remove the plastic junction box on the right side of the carb which would allow you to replace the pulley cover more easily if you want to use it.

Also you might want to get an adjustable pilot air screw for the sort of ratted one in the photo. it is the long brass piece in the rear behind the main jet with a screw driver slot in it. They are about $11 and then you can adjust the pilot air for starting in cold and hot weather quite easily.

To clariry a few points. The adjustment screw you refer to as an air screw is a mixture screw (usually refered to as a fuel screw). It is not an air screw. The oil/vapor box you suggest replacing with a "T" junction should never be removed. Leave it in place. Yes the coast enrichener (CE) can be remioved. When doing so, the nipples on the carb need to be connected with a hose. The nipple on the head is capped. If the nipples on the carb are capped, the 60 pilot air jet needs to be replaced with a 100.

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