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84 XR 250 carbs

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I have a 84 xr 250 with a broken carb and need to find a good used set. I got skunked on a set from ebay :cry: Stupid slow computer! Does anyone know of any other years or models that will work? Any help i can get on this would be great. Thanks

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No, the 84-85 have a dual carb setup. The 84 is PD41a IIRC.

The carbs can be found around, sometimes a really clean set shows up on ebay but they are expensive.

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I finally got a set on e-bay for $26.10 :cry: Does anyone have any advise on if i should change the jets before i put em in? Or anything else i should do to them besides a good cleaning? Thanks.

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81 thru 84 models share the same carb: Keihin PD71A, according to my Haynes manual. Appears to be unique to the XR250

No the 84 through 85 are the same. These were totally different than the earlier single carb models.

Personally I advise folks to avoid the 84-85 XR200 - XR250 models as these were the worst XRs ever built. I am surprised that any are still running.

Dwight

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I now know that these are the worst of the XR's and thats why i want to make it run good so i can sell it and get somthing better. The bike is really clean and has a fresh top end. I would like to have it in good running condition so it won't blow up on the new owner. So bring on the good jetting onfo please!

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I have owned two of these bikes (both '84 versions) so I have experience in how to rejet the carby's, albeit after many long hours in the shed!

The following settings assume the engine is standard.

Check that your float heights are at 19mm for both carbs. To check this, tip the carbs over backwards and measure the distance from the float bowl mating surface to the edge of where the floats stick out, the original setting is 18mm but having the floats 1mm lower will let the bike run crisper as they were rich standard.

1984

Main jets- Primary carb (left-hand) 108

-Secondary carb (right-hand) 105 (you may need to go for a leaner 102, testing will tell)

Needle clip positions- Middle position in both carbs

Pilot jet- 45

Airscrew opening- 1 1/4 turns out

1985

Main jet-Primary carb- 108

-Secondary carb - 98 (note smaller than '84)

Needle clip positions and pilot jet size are as with the '84 version although the '85 used different needles and needle jets.

Airscrew initial opening- 1 turn out

Other than checking these settings, give the carbs a good clean and make sure the anti-splash guards are fitted over the main jets in both carbs. Also make sure the second carb doesnt open till the primary carb is approx 1/4 open and you'll do fine!

Hope this helps

Mark.

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what FAQ on the 400?

I'm curious what changed from 86/87 to 2004 on the XR250's

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