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Keihin PD Super Pumper Carb/ TURBO

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21 hours ago, mixxer said:

Well now you've jolly well done it, Michael!!

That carb is a cleaner/ simpler design ...

30mm out of the box... With accelerator pump....

 

An xr200 manifold maybe would adapt it, but if not , an adaptor would be simple to fabricate...

Where were you a couple weeks ago when all this started?? Lol

Sorry, my bad, I thought this might be the same carburetor and cable I had been eyeing up for some time.

I like the fact that you can adjust the accelerator pump timing on the one I posted the link to and it comes with a choke

which is more important for XR200R owners, due to kick start vs. Estart for you CR230F Guys. 

 

I still want to get your impressions after you are done, so I am following with interest.

I just wanted to get some feedback, as to the feasibility of any performance benefits of a pumper carb

as the heritage of the engines are shared to some degree. My biggest complaint with the XR200R is it's

inabilty to "wheelie" on demand, i.e. you come across a log out of nowhere and you need that little bit

of grunt, or torque to unweight the front end. It's not there, even with a performance exhaust.

 

It was my hope, that potentially a pumper carb would give it that little boost she needs.

 

Thanks again for the thread, good read.

 

Michael 

 

 

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2 minutes ago, KTM520EXC said:

Sorry, my bad, I thought this might be the same carburetor and cable I had been eyeing up for some time.

I like the fact that you can adjust the accelerator pump timing on the one I posted the link to and it comes with a choke

which is more important for XR200R owners, due to kick start vs. Estart for you CR230F Guys. 

 

I still want to get your impressions after you are done, so I am following with interest.

I just wanted to get some feedback, as to the feasibility of any performance benefits of a pumper carb

as the heritage of the engines are shared to some degree. My biggest complaint with the XR200R is it's

inabilty to "wheelie" on demand, i.e. you come across a log out of nowhere and you need that little bit

of grunt, or torque to unweight the front end. It's not there, even with a performance exhaust.

 

It was my hope, that potentially a pumper carb would give it that little boost she needs.

 

Thanks again for the thread, good read.

 

Michael 

 

 

Very welcome Michael, always glad if I can help...

I had built an xr200 as an xr212 in the mid 90s, for my wife to ride Michigan woods on...

It turned out to be the bike with the longest waiting list of guys to want to ride if she was going to sit out for a loop... Light , agile, fast in the woods...

Scott's was doing suspension then and they did a wonderful job on this bike...

Let me see if I can pull some engine details from my rusty memory... 

Powroll was still in business and I had them do a stroker crank for me... I believe I stayed stock bore and got to 212 on stroker alone...

The 200s aren't really 200cc, like the 230 isn't a 230....

I had gotten a wiseco piston in something like 12:1... Even though wiseco doesn't list one for the 200... It was one for a 185 that when you went up to the 185 overbore that matched the stock 200 bore, it was a hone and drop in affair... Someone like forum member Chuck would for sure know the details...

The cam I used was cataloged by white brothers and was actually ground by Web...  I want to say duration was like 244 degrees... An all around torque cam...   

FMF exhaust and dialed in jetting...

Can't say enough good about how the bike ran... It was a Giant Killer in the woods.... 1st through 3rd was great for wheelies over roots and rocks etc..

I would say skip the stroker and add the rest would drastically change the personality of the 200 for you...

And for certain... A pumper carb does pull harder/sooner with the pump shot filling in the fuel supply gap for fast throttle opening...

What do you have on the 200 already??

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mixxer,

 

I have a XR's only header and the steel SuperTrapp 3" muffler, so flows quite well, although I wish it was quieter. 

I also have the timing fully advanced, other than that, that's about it for the motor. I have rebuilt the shock myself and 

put in PC1 shock oil, big difference and have installed an 43mm conventional XR400 front end with gold valves.

 

I ride in altitude from ~ 2500 ft to 5500 ft, hence the fully advanced timing.

 

I have (4) XR200R's (2) 90's and (2) 87's and an (1) 02 KTM520EXC. I love the light weight and traction 200R's 

have, if I have one complaint, it would be it's ability to lighten the front end in those "oh crap" scenarios. 

 

For me it just started out as a play bike to take camping and grew from there due to the "fun factor".  At the

end of the day, that's what it's all about, I no longer have any desire to go racing or screaming out in the desert

at 100mph+. Quite happy at my Camp Ground and (2) places I go riding in the Northern CA Sierra Foothills.  

 

Michael 

 

 

Edited by KTM520EXC
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1 hour ago, KTM520EXC said:

mixxer,

 

I have a XR's only header and the steel SuperTrapp 3" muffler, so flows quite well, although I wish it was quieter. 

I also have the timing fully advanced, other that's about it for the motor. I have rebuilt the shock myself and 

put in PC1 shock oil, big difference and have installed an 43mm conventional XR400 front end with gold valves.

 

I ride in altitude from ~ 2500 ft to 5500 ft, hence the fully advanced timing.

 

I have (4) XR200R's (2) 90's and (2) 87's and an (1) 02 KTM520EXC. I love the light weight and traction 200R's 

have, if I have one complaint, it would be it's ability to lighten the front end in those "oh crap" scenarios. 

 

For me it just started out as a play bike to take camping and grew from there due to the "fun factor".  At the

end of the day, that's what it's all about, I no longer have any desire to go racing or screaming out in the desert

at 100mph+. Quite happy at my Camp Ground and (2) places I go riding in the Northern CA Sierra Foothills.  

 

Michael 

 

 

At higher altitude you can make good use of higher compression ...  And likely be more than fine for pump gas

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7 hours ago, mixxer said:

At higher altitude you can make good use of higher compression ...  And likely be more than fine for pump gas

Yes of course you are correct, but again, our 200R's are kick start, so the kick start gears will stress more and they are in the

center case, so if they go south, then you need to split the cases. My experience is that once you make one modification, in order

for that (1) modification to work there are a series of modifications that need to follow, that lead into somewhat of a money pit. 

 

I love the simplicty of our 200R's, they are light weight from factory, bullet proof if you keep on your maintenance. In our 

forum we have found ways to remove weight, plaggerizing from other XR models weight saving ideas, via Chuck. I spoke with a

reputable engine builder and he stated, that an air cooled motor should not exceed 10:1 compression due to it's cooling

limitations vs. it's water cooled counterparts and his specialty is Supermoto, so I always took that to heart. 

 

I have already cracked the suspension portion, which to me is far more important than building the engine first. I.e., if your

engine outperforms the suspension, what is the point. For me, from a performance standpoint, save any carb mods, 

would be to put in the next level cam shaft, have the icylinder head modified and to install bigger intake and exhaust valves. 

At this point, even though Chuck is super big fan of the stroked 218cc, me personally, i think it stressing all the residual parts

too much. I have read where owners of stroked 200R's are replacing transmissions every other year, love the power, but hate 

the repair bills.

 

Any rate, this your thread, keep it your thread, you are putting in the work and helping other CRF230F riders with a potential mod

that will suit there bike that will make them happier,  I just wanted to thank you, as it's potential, interests me. I am rambling too much,

so if you want to, you can PM me, as I am backing out of this thread and am just a spectator and waiting anxiously for the end result. 

 

Good Luck and hopefully good results. 

 

Michael 

 

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Those people wrecking their transmissions would probably kill them if they had standard engines. They can fit ATC200X 5 speed gearboxes straight in and are much stronger.

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8 hours ago, KTM520EXC said:

Yes of course you are correct, but again, our 200R's are kick start, so the kick start gears will stress more and they are in the

center case, so if they go south, then you need to split the cases. My experience is that once you make one modification, in order

for that (1) modification to work there are a series of modifications that need to follow, that lead into somewhat of a money pit. 

 

I love the simplicty of our 200R's, they are light weight from factory, bullet proof if you keep on your maintenance. In our 

forum we have found ways to remove weight, plaggerizing from other XR models weight saving ideas, via Chuck. I spoke with a

reputable engine builder and he stated, that an air cooled motor should not exceed 10:1 compression due to it's cooling

limitations vs. it's water cooled counterparts and his specialty is Supermoto, so I always took that to heart. 

 

I have already cracked the suspension portion, which to me is far more important than building the engine first. I.e., if your

engine outperforms the suspension, what is the point. For me, from a performance standpoint, save any carb mods, 

would be to put in the next level cam shaft, have the icylinder head modified and to install bigger intake and exhaust valves. 

At this point, even though Chuck is super big fan of the stroked 218cc, me personally, i think it stressing all the residual parts

too much. I have read where owners of stroked 200R's are replacing transmissions every other year, love the power, but hate 

the repair bills.

 

Any rate, this your thread, keep it your thread, you are putting in the work and helping other CRF230F riders with a potential mod

that will suit there bike that will make them happier,  I just wanted to thank you, as it's potential, interests me. I am rambling too much,

so if you want to, you can PM me, as I am backing out of this thread and am just a spectator and waiting anxiously for the end result. 

 

Good Luck and hopefully good results. 

 

Michael 

 

Oh no Michael, you're not backing out that easily...lol

 

I will have the pumper carb hooked up and tested this weekend for sure..

 

I want to clarify a bit about air cooled and compression ratios..

The static mathematical compression ratio doesn't really count for a whole lot.... It doesn't tell you much about what's really going on for cylinder fill, actual dynamic.compression, or power output...

Examples...

If you have a turbocharger running 40 pounds of boost, and you have 8:1 static compression and 4 valves per cylinder....  You are likely packing a serious charge into the cylinder ...creating a lot of dynamic.comprssion... And power output and heat load are quite high...

Now... Take a 2 valve per cylinder , naturally aspirated, mildly cammed , 10:1 compression engine .... And put it at high altitude where the air is less dense... And what are you actually seeing for dynamic compression or specific power output??  The answer is "not much"....  And not much comparative heat load either...

So in the real world....  Until you did a lot of things from cam and porting and valves , etc... You can simply bump compression in an xr200 , and not worry about much.... It's when you are filling the cylinder closer to the max volume that you need be concerned with overall compression....

A 12:1 squeeze of not much charge , is still not much pressure

 

 

 

Edited by mixxer
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Ok... The results...

In a minute.... First off a couple more hurdles....

Fuel inlet spigot was straight and wanted to hit the frame... It's press fit , so I pressed it some more.... Problem solved...

Next, the holes where the throttle cable ends go needed to be filed a bit...

And a small part of the right side panel (that you don't see) needed a trimming to clear the accelerator pump linkage...

120 main... Needle 4th clip...42 pilot... Idle fuel screw out 1.5 turns from seated... Choke removed...

Fires up with one pump of the carb and just hit the button...

110% no question at all... Bike is WAY more AGGRESSIVE and responsive with this carb...  Noticeably more power and sharper / stronger pull... Dramatic!!!

Love it... Wont go back, ever!!!

And everything felt "fine" with the stock carb... Good pull and response .... So I was already starting to tell myself not to expect much improvement...  Lol... Wrong!!

Edited by mixxer
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5 hours ago, Baja Rambler said:

Are you gonna carve out the venturi some more?

I can't get any more slide lift..

 I had to cut he throttle stop to the max to get an extra 2~3mm already... I'm outta rope...

But I know I have made it larger than OEM by close to 3mm.... And I know total CFM has gone up from the unobstructed intake bell via removal of all the choke hardware....

It pulls very differently now, as well as runs out better on top ... Hard to convey the difference in personality without someone riding it firsthand.....

Powerslide and wheelie ability sharply enhanced..... Fun factor MUCH improved

 

Edited by mixxer
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And a pic of the new turbocharger....

I pulled out choke plate axle and epoxy filled ... And then cut off all unused flanges and protrusions... Love the whole clean look...

So... Wolf in sheep's clothing... Lol...to the untrained eye it looks like the stock mixer.... But... The trained eye then says : " wait a minute!! Is that a super freakin trick azz turbo accelerator pump I'm lookin at?!?!!". Hmmmm, something tells me this ain't no ordinary foo foo bike I'm looking at...

And then you notice the gorgeous shaved cooling fins..  😱😱... And the powder coated white frame😎...

And start to realize there could be no end to the trickness of this sexy hunk of machinery known as Bunny...😁

Sweet XR legs coming soon.... Rebuilding and valving ,,, plus lower fork legs are off for black powder coating.... Is there no end to the sexiness?!?!????

 No, not bloody likely....🤘

IMG_20170813_101117671.jpg

Edited by mixxer
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Lol:
There is no dirt on the bike.
No dirt in Tennessee or you ride on the pavement.

Yes it looks great, and I believe your going to the dyno room soon?

Looks like I need a minimum of a 30mm carb up to a 32mm carb with an AP....any suggestions.... (I too love the stealth look)

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2 hours ago, adnohguy said:

Lol:
There is no dirt on the bike.
No dirt in Tennessee or you ride on the pavement.

Yes it looks great, and I believe your going to the dyno room soon?

Looks like I need a minimum of a 30mm carb up to a 32mm carb with an AP....any suggestions.... (I too love the stealth look)

Ha-Ha... I'm a fanatic about cleaning my toys before I put them away...

My friends have always been bagging on me about my clean freak status with my bikes... I like to point out the distinction between mine and their mounts ... " It's DIRT BIKE... not DIRTY BIKE"...

Tennessee has this gawdaful clay that might as well be brick red paint for how bad it adheres to everything....  I have to alternate between penetrating oil as a pre soak.... To simple green degreaser on the second round to deal with the oil... To even get the bikes remotely clean.... 

Guy, I was unaware of the PD pumpers for forever..  I caught a thread where I read something like someone using a 30 or 32mm PD pumper from maybe an xl350... on an xr250...  I thought it was stevethe when I posted the first thread to get more PD Pumper info.. and Steve told me it wasn't him...

Then Ricky said he was going to try one from an xl250... And when I searched that on eBay, a whole bunch of knock off new PD style pumpers came up...

After riding and feeling the dramatic difference in the aggressive nature of throttle response, I thought it must be what you guys are experiencing from your pwk carb conversions... With the sharper/ quicker response from the flat slide design.... I thought " no wonder they like them soooooooo much!!"

I can't imagine how fun your full tilt boogie monster bikes are....

I'm telling myself BBR piston for a 10cc + compression bump... And an oversize intake valve and I'm done... Walking away from the Performance Cocaine table...

But man o man did this carb ever sharpen the teeth of all the other mods on my little bunny...!!! 

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I had used the needle supplied with the carb... Clip on 4th notch down from top...

And this main/ pilot jet kit:

120 main

42 pilot

 

Screenshot_20170813-141647.png

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mixxer,

Well done and congrats on a successful modification, it has certainly inspired me to try this on the lil 200. 

Michael 

 

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One thing still available on tuning pump shot timing and pressure...

Same sort of thing as on FCR carbs...

The plunger action on the diaphragm is not "direct from throttle input"  ... I have always thought it was meant to help prevent pump diaphragm rupture from too much pressure.

The throttle motion on an FCR actually allows for a cam to move and allow a second spring to put pressure on the plunger... Not direct throttle actuation... A popular mod for response in the FCR world is to use a zip tie to slave the throttle and plunger action directly ... People use it successfully although I have not wanted to adopt such a harsh connection.... Instead of a zip tie I have used an o-ring as a moderated connector of sorts... More pressure than the plunger spring alone, but still an element of give to it...  Works great.. no failures experienced...

The accelerator plunger setup on the PD style carb uses a spring linkage between the throttle and the pump arm that moves the plunger... You pull the the throttle and then a spring from it pulls the accelerator pump arm...

You can easily add an o ring between the 2 points where the spring connects.. and the o ring would assist the spring in creating more accelerator pump pressure... Stronger shot... But that ends up being felt as added resistance in the throttle...

Also there is a tab that limits total plunger arm travel... You can adjust that tab to allow for a larger volume pump shot...

Those are 2 more areas you could potentially fine tune for the perfect pump shot for your application....  More pressure/ greater volume....

I am very happy with my setup at the moment and haven't played with those options yet... But they are there, should someone want to...

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My interest was Piqued, so I looked them up on Ebay. 

Found them sure enough, but all are in the USA. Roughly A$50 PLUS A$55 for freight! :facepalm:

Oh well......

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That's a bummer... They must be unloading chinese freighters by the boxcar over here... A bunch of places selling them... I got mine shipped for $43 total... But since then I have seen them for $38 shipped.. 

I have to wonder what the hell would everyone need with so many carbs??

No need for rebuild kits... Just throw your old carb in the trash and put another disposable carb on...?!?

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