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33mm vs 36mm carb Thoughts?

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Ok I have a 1995 DR350se. Bone stock except for K&N air filter and I opened the top of the airbox some to make installing the K&N filter easier. Bike runs fine plug is golden brown. I despise the street model vacuum carb that is on it. for no other reason than the nightmare it was on my last DR. Fuel cock was leaking when I bought the bike so it has already been replaced with a dirt model one. I have been looking at installing a TM33 dirt model carb. Place I was looking at to order a whole TM33 kit is out of stock right now. Talked to a guy there and he recommended I get the larger 36mm kit (in stock and $70 more) he keeps saying that the 33mm chokes it off from the factory for emissions and the 36mm will run just perfect and not hurt the bike at all. I have always thought the 36mm was good for the big bore kit and wouldn't be good on a stock bike. I would really like a second and third, fourth.... opinion. 

36mm kit "might" not work with the airbox boot and have to use a pod filter, which I do not want. bike lives on the street 90% of the time but with rain, and that 10% mud and fun, I just don't want to lose that box. guy I spoke to is looking into the boot still fitting right now.

would love to hear anyones thoughts.

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Ok I have a 1995 DR350se. Bone stock except for K&N air filter and I opened the top of the airbox some to make installing the K&N filter easier. Bike runs fine plug is golden brown. I despise the street model vacuum carb that is on it. for no other reason than the nightmare it was on my last DR. Fuel cock was leaking when I bought the bike so it has already been replaced with a dirt model one. I have been looking at installing a TM33 dirt model carb. Place I was looking at to order a whole TM33 kit is out of stock right now. Talked to a guy there and he recommended I get the larger 36mm kit (in stock and $70 more) he keeps saying that the 33mm chokes it off from the factory for emissions and the 36mm will run just perfect and not hurt the bike at all. I have always thought the 36mm was good for the big bore kit and wouldn't be good on a stock bike. I would really like a second and third, fourth.... opinion. 
36mm kit "might" not work with the airbox boot and have to use a pod filter, which I do not want. bike lives on the street 90% of the time but with rain, and that 10% mud and fun, I just don't want to lose that box. guy I spoke to is looking into the boot still fitting right now.
would love to hear anyones thoughts.


TM33 is what was fitted to the dirt bike models. Likely there was no emissions on the dirt bikes in the mid 90's but that is solely conjecture on my part. Everything to make this carb fit your bike is completely OEM with one exception and that's a spacer needed to move the carb back and clear the starter motor. On top of that you'll need the following parts from a dirt model DR350: intake manifold, airbox boot (the big schlong going to the airbox), and throttle cables. The TM33 routes the throttle cables down the right side of the bike. This would essentially be a "bolt on" upgrade so the question is just what kind of upgrade do you want? Do you want to custom make a carb, it's mounting and jetting? Or you can buy a TM33 from Amazon for ~$220 and it's properly jetted and ready to go right out of the box. I just did this to my project called Blue Bike.

http://advrider.com/index.php?threads/dr350-fun-build.1166102/

IMG_20170326_172315.jpg

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Last time I bought a carb off of amazon it was a cheap knockoff and never ran right so that is why I was looking at specific kits for the bike from known builders. Jesse (Keintech) is now retired he recommended ThumperRacing but it looks like they no longer do carb kits. so my next thought was powerbarn. I am looking at his TM33 kit vs TM36 kit. I just want to know if the 36mm is too big to get to run right on the stock bike. I am not really looking for more power. My main concern is reliability. 

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reliability:

stay away from anything non-stock like a 36mm, that would be a huge mistake.

ditch the k&n for a good foam air filter & close up airbox to stock

most of the dickin around with carb jetting & needle height is due to opened airbox

non-vacuum petcock is a move in the right direction

 

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this guy fitted a fcr37 to his DR350 so a mikuni tm36 might work, his was a kick start model though, think getting around the starter motor would be a problem

 

Edited by paint it black

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On 3/31/2017 at 10:24 AM, paint it black said:

this guy fitted a fcr37 to his DR350 so a mikuni tm36 might work, his was a kick start model though, think getting around the starter motor would be a problem

 

Yep that is me, and it works great, BUT there was a lot of jetting work involved so I would recommend sticking to the tried and tested 33mm on a stock bike.

 

The reason I spent so much time getting the Keihin FCR to fit and work is that the throttle action is a lot smoother as the carb has rollers on the slide. But I have not yet figured out how to fit it to an electric start DR as that would be the perfect set up!

 

The CV carb is actually very good, simple and easy to work with, the problem is that these bikes are quite old now and ANY carb fitted will give problems as o-rings etc deteriorate so it just comes down to maintenance...

 

 

 

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