Knock Off FCR 39 Experiment on a Brand New DRZ400SM! It works!

[@BubbaB43]

I can attest to the float height issue with these knock off FCR's! Same iss on a race kart I had. I installed a FCR 28mm slant on it and it was absolutely terrible. I spoke to a FCR specialist and he suggested checking the float height because they are "super sensitive to float height". After checking it and confirming it was out by 2mm It ran like an absolute beast!

[@nvmcrider8475]

Great at video that answered a lot of questions.

[@artiexr222]

Great informative vid Dewey looking forward to seeing how it lasts in the long term.

[@rockshoezzz862]

Awesome! Going on week two and the carb is still doing its job! ! Awesome upgrade 😁

[@jessecrawford2711]

After listening to the end of the video that needle definitely needed dumping to c2. Get him a DVR from jets r us it will do good

[@jessecrawford2711]

I imagine if you put a afr gauge on there you would find most recommendation for jetting the drz it's way junky rich. Probably in the tens. I run a 148mj and 35pj with 150 main air jet and 3/8 turn on my pas. And my afr lives between 11.2 and 13.3. at wfo my afr is 12.3 to 13.6. read Taffy's areas of influence on thumper talk after following his advice and then confirming it with my wideband kit every body is way rich on the drz. Your losing a lot of power and gas mileage. I get 50mpg with a big bore hotcams full exhaust and I smoke my buddies crf450l but I couldn't when I ran traditional jetting.

[@DRZWhisperer]

Thanks for your valuable input and I Apologize for the delay or on the reply. I'm a firm believer that there's no real cookie cutter for jetting but their recommendations are a good place to start

[@samuelcabe3372]

I want to get the FMF header pipe. I currently have a TBR Carbon slip on. What exactly needs to be done by the muffler shop to make it fit? Any info is helpful I can’t find anything online when researching

[@DRZWhisperer]

Your two brothers slip-on is made to slip on to a stock header. That means that it's slip on portion where it's supposed to slip over the header pipe is too small to go over a Power bomb header. You need to remove the two brothers slip-on and bring it to the muffler shop along with your FMF Power bomb. They will use their exhaust pipe expander to stretch it to the proper size so it will slip over the top of the header and you'll be good to go. Pro tip 1, use red RTV at the slip-on section to get a better seal. 2. A symbol different components of the exhaust loosely on the bike and slowly tighten them down evenly to keep them from getting in a bind.

[@sswayne1]

What size jets did you end up using? Would you recommend the stock needle that came with the carb? or was the JD needle better?

[@DRZWhisperer]

I would go with JD recommendations as if it was a real FCR and use their needle

[@brandondickson4406]

How much did the Fake Fcr39 cost? Was it more responsive than the stock carb with the JD Jet kit? Thanks just wondering

[@DRZWhisperer]

It was a little under $150 plus the adapter parts in total around $200

[@oliverkoehne7978]

I appreciate this video I see while installing the new carb you still left the pair valve on the bike utilizing vacuum port on the engine intake. I need help, I am debating doing that myself with new bigbore build. From my understanding the pair valve adds air into the exhaust, allowing me to shoot flames out of my rs2 uncorked with stock carb I’ve replaced the vacuum petcock therefore my sole reason for wanting to keeping the pair valve with fcr39 is to shoot flames periodically Since this video Have you experienced any excessive decel popping or “backfires” utilizing the continues vacuum from engine intake

[@DRZWhisperer]

There are some follow up videos where I delete the pair valve on this bike and replaced the petcock as well as at kick start and e cams

[@oliverkoehne7978]

⁠​⁠@@DRZWhispererI appreciate your time and response. yesssir those where very informative aswell, I did go ahead and watch those too. I also notice you removed it I supose my main worry is doing the 30 min break in with the pair valve hooked up to engine intake causing possible issues Correct me if I’m wrong, this is all new to me. I belive the stock carb vacuum connection is ported vs continues vacuum from engine intake. Did you notice a difference with the pair valve blocked? In your opinion Would you say it is OK/safe to get my bike running with the pair valve for now and decide to block off later? Or weather just get it over with right now

[@DRZWhisperer]

@@oliverkoehne7978 you will be fine with the pair valve. We noticed less deceleration pop with it deleted but that is after internal combustion. If you delete all vacuum you will need to just cap the nipple on the carburetor if you use the stock carburetor

[@Syntax152]

What jets you decided on that stock bike ? Also seems like when you hold the throttle steady bike surges a lot, were you able to fix that issue ?

[@DRZWhisperer]

If I recall correctly we did a float height adjustment and since he was going with a full exhaust and FMF header with the DG slip-on that we expanded I think we went with the 165 and 45 needle setting third position. We are at about 1100 ft

[@Syntax152]

@@DRZWhisperer is the surge gone after float height adjustment ?

[@kurthedgecock6313]

Good video. Do you any experience with an lectron carb for the drz?

[@DRZWhisperer]

I don't have any experience with a lectron on a DRZ but I tried one on my converted Yamaha Supermoto and had a lot of idling issues.

[@kurthedgecock6313]

I have drz with full exhaust and the factory carb properly jetted. It sounds great buy the performance is lacking. I don't want an fcr carb. The other options are lectron and possibly a mikuni tm 40. I won't be doing the work. I know better than to try. My dislike for thr bsr 36 intensified when I purchases a Honda crf 450rl. I'm open to suggestions from an experienced mechanic like yourself who knows the drz well.

[@DRZWhisperer]

@@kurthedgecock6313 I would recommend the authentic fcr 39 and get a brand new one. These replicas or knock-offs copies whatever you want to call them is they can be quirky. Make sure and do your due diligence when she's going to set for a while and drain the bowl and you should be okay. Regarding the crf450rl, they have their own issues with flame out in some cases where people are depending on quick throttle response in certain low RPMs. Electronically they are trying to control the emissions in the same way the stock carburetor on the DRZ does and mechanically changing it with the proper jetting and needle helps but the fundamental flaw is still there. On the CRF mini of the suggestions or the cocktail of solutions is the vortex ECU and full exhaust because the problem is endemic within its factory ECU that cannot be flashed or reprogrammed. The factory carburetors restrictive on the DRZ and has a delayed reaction due to the throttle body type apparatus opening and waiting for the demand of the engine to force the slide to pull up whereas the lectron and fcr both open with the throttle cable immediately. The Lectron is an improvement but can have idling issues and limits top end a little whereas the throttle response with the fcr is going to be crisper due to the accelerator pump and the top end power will be increased. It may hurt the fuel economy somewhat but it is worth the money. Single-handedly the best performance mod a person can do even with a stock exhaust

[@markalan4026]

@@DRZWhisperer Man, I really want a FCR 39 carburetor, but 1,000 bucks is very difficult for me to justify. IMO I think somewhere around 600 would be a more appropriate price for that carburetor.

[@DRZWhisperer]

@@markalan4026 if you were local I would throw one if these on there for you

[@smalltownrider5603]

Did you ever have a hanging idle issue? I couldn't ever get that to go away. No air leaks and tried many pilot jets and no throttle cable bind.

[@DRZWhisperer]

I did not have any hanging idol issues. Did you idle it down with the idle speed screw (not trying to insult your intelligence). Is there a chance that the hot start is not sealing? What sizes of pilot jets did you use? Did you inspect the pilot Jets? There's a possibility that there could be some material in some of those jets like some burrs for example? Did you try adjusting the mixture screw?

[@smalltownrider5603]

@@DRZWhisperer I tried it a while ago so I can't really remember the sizes of the pilots. I did idle it down and made sure the pilots were clean. I had 2 different drzs that I tried the carb on and it still had the hanging idle. Long story short I got pissed and chucked it at the ground lol. I'm tempted to try it again after seeing this

[@DRZWhisperer]

@@smalltownrider5603 tuning can be challenging. It's also the luck of the draw with these carburetors. The manufacturing is obviously a Chinese copy. You might have had a bad carburetor. These things are very complicated and also very simple at the same time when something very simple is off It causes big problems. Check out Link's Garage video that he recently released of the other popular knockoff carburetor. We collaborated with lots of messages back and forth to get this thing working for him. I like the fact that on the back side of the carburetor the air box side that you can remove the red bell that some people just trim down to fit the air box and replace it with a metal adapter meant for the authentic FCR carb. You might have to do a little bit of research to find the correct housing but it can be done or you can just do your initial trials with a shaved down red Bell or you could even do what he did in his video which seems to be working for him. I think that model is even cheaper. When you had your hanging idle, did you hook up the vacuum petcock?

[@smalltownrider5603]

@@DRZWhisperer ok thanks I'll check it out. I ended putting on a aftermarket petcock that didn't rely on vacuum just gravity. My second drz I used the stock petcock and hooked up the vacuum line

[@DRZWhisperer]

@@smalltownrider5603 I'm sorry that you had trouble, I think if I remember how this video went I think I said trying this was a gamble and maybe we got lucky. Please follow up and share your results. Good luck

[@jarvislarson6864]

I have a 01 ktm 400exc can I upgrade to newer version fcr 39?

[@DRZWhisperer]

That is a good question. I'm probably not the most qualified to answer that. I would definitely search the forum thumper talk to see what they do then you will know from people with experience with that manufacturer.

[@MrKidkiller159]

Your bike has the good cab. 👍

[@WhosJohn]

Really wish there was a lectron clone

[@DRZWhisperer]

There is and it's called smart carb, but they are expensive as well

[@supermoto_problems]

Do you have a link to your 3D printed part?

[@DRZWhisperer]

www.ebay.com/itm/174252768613?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=48tNtj0TSKG&sssrc=2349624&ssuid=J8OyNfPlRNi&var=&widget_ver=artemis&media=COPY Keep in mind you will still need the teat for the vacuum for your pet car that goes on your intake and your boot to adapt the carburetor to the head needs to be an E model

[@supermoto_problems]

Thank you my good sir! It's been ordered 😃 Got one more thing, do you have the boot (intake manifold) from the YZ400f or do I go with the Suzuki E boot( P/N 13111-29F00) ?

[@DRZWhisperer]

@@supermoto_problems that boot should work It did for me the tab slots might be slightly different but it should work

[@supermoto_problems]

Im back with another question... how did you go about the oil catcher?

[@DRZWhisperer]

@@supermoto_problems please provide more context to your question please

[@rrazote2279]

I used the fake FCR with the red bell housing. It's based off the gen 1 FCR (non-MX). I ran into 2 issues: firstly, the throttle cable holder/bracket is too long and hits the bike's frame - need to cut out a chunk of it for fitment. Secondly, the stock SM cables are too long. You do also need an intake adaptor. I ended up having to grind down about a millimeter around the cast aluminum one I got so that it could fit into the intake boot. I was going to order new throttle cables, but may instead, opt for this one as it looks like a better fit. Is this the Chinese FCR-MX model, or something different? Did you have to swap anything else out besides the jets and intake adaptor (cables, etc?) I saw that this one has a TPS sensor, did you end up using it? Thanks in advance!

[@DRZWhisperer]

If you look at the thumbnail you might be able to see it but I have a 3D printed intake adapter that is available on eBay it it fits over the top of the non-removable housing that on an authentic one is removable. As the instructions that came with the 3D printed adapter for the air box boot alluded to I used black RTV to seal it around the aluminum surface. There are small set screws around it so that you can keep it in place while it cures so that it does not move and obstruct the alignment of the air Jets. This side of the carburetor would fit right up to an e-model. I used a rubber boot for an e yz400f to adapt It to the Head but otherwise you would need to get an e model rubber boot to adapt the carburetor to the Head and appropriate clamps as stock will not work. An alternative to this would be just a standard hose clamp

[@DRZWhisperer]

I also got the tit or hose barb for the head to make the vacuum petcock work and I got an authentic OEM part for that. This is an fcr MX type clone with the non-removable airboat side coupler.. if you listened or watched the video I did not show it but I mentioned it that I changed the float height on the carburetor to fcr specs of 9 mm as it was filling the bowl too highly with fuel it basically had no float height or a zero or 1 mm measurement. I used the stock throttle cables but on the top throttle cable I had to cut a slot out in the carburetor to fit it directly in as described in the video. This does have a throttle position sensor and I did plug it in. I used a JD style cold needle because the taper on the needle that was installed was fairly flat rather than the more aggressive angle of the JD style cold needle. I used JD tuning specifications for the exhaust and intake modifications 3x3. With the 3D printed adapter for the air filter side it made the carburetor just a little bit wider which made it a little bit more difficult to get into position however once located into position it sets much better than an fcr MX which I kind of like.

[@rrazote2279]

@@DRZWhisperer Sorry Dewey - Got excited on the prospect of finally moving my FCR conversion project along, after it stalled back in May. I did see the rest of the video regarding the float height. While my long term goal is to get a Sudco (maybe a rebuilt one), I was going to try one of these along with a cam upgrade and Athena kit. Thanks again for the info!

[@DRZWhisperer]

@@rrazote2279 to be honest I would try this alone rather than more than one thing at once. This guy did just put an FMF header on at the same time. I also mentioned it was a similar adaptation that I did on mine. A very easy job for a exhaust shop versus the way I did mine which was by myself with a crappy exhaust pipe expander and a lot of swearing but I got it done. I think this way you could appreciate the performance of grade of each thing individually. The owner of this bike's reaction to the improvement of throttle response was very excited and he has been keeping me updated and said that going down the highway at 55 to 60 MPH seems a little bit more effortless for the machine. All he has done is the exhaust and 3x3. This is quite possibly the best upgrade a person can do for the money other than an authentic fcrmx which would be also the best of grade for the money

[@rrazote2279]

@@DRZWhisperer I totally get that. My problem - and it is a sickness - is that I love to tinker with my bikes. I literally bought a Honda Monkey and swapped out so many parts, I got addicted to wrenching. I got rid of my Z900rs, just because "just riding it" was too pedestrian for me XD. It's not the power, it's the learning process and knowing that I could literally do my own work on my bike, coax more power into it, adjust suspension. I ride like a granny (and like to gymkhanna once in a while), so I'll never really be able to "appreciate" the power the cams or athena would offer - BUT, knowing I did the upgrades myself is my reward. I know - I'm weird. They're going to be upgrading the bike in the next few years. I have a feeling fuel injection and 6 speed is on the table. I doubt I'm going to go that route as I love modding this one too much.

[@MrKidkiller159]

Just use a crf450 carb. It fits and you have factory jetting base.

[@DRZWhisperer]

I have seen people use used carbs off of other bikes and it seems to work for them. This was just an experiment to see just how good one of these can be and I'm pretty impressed with how well it works

[@MrKidkiller159]

I agree with wondering how the China stuff works. It's entertaining