'03 gas tank for sale

[Norm Keller]

I would expect less lag from the Mikuni because there throttle is opened directly. I would expect better low RPM response also, due to the smaller bore carb since air flow velocity is higher but that it will lose out on maximum power for the same reason. Since that's not always the case in practice when comparing different models of carb, I'm interested as to the results.

[Martin Earl]

Does the carb kit include a throttle cable or do we use the OEM KLR cable? [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2F2016%2Ficons%2Ficon-envelope-tick-round-orange-v1.png&t=1571810451&sig=_SPzIOC7DsOWzPSs.ZucEQ--~E[/img] Virus-free. www.avast.com

On Fri, Mar 25, 2016 at 1:35 PM, 'Fred Hink' moabmc@... [DSN_KLR650] DSN_KLR650@yahoogroups.com> wrote: I sold a Mikuni carb kit and an Air/Fuel Ratio Monitor to jettin Jim who said he was going to run his KLR before and after on a dyno. So far I have not heard any results. I doubt there is going to be much difference and any difference should be the result of the jetting that has been chosen. The Mikuni carb s advantage is not in making more total horsepower but the drivability of the bike and having more power down low in the power-band can be felt in your seat of the pants dyno. Fred http://www.arrowheadmotorsports.com [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Friday, March 25, 2016 12:11 PM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] [DSN_KLR650] Re: Carb Conversion Just wanting to close the loop of "I wonder". Has anyone made a quantitative comparison as to maximum power between the two carbs?

[Fred Hink]

Although the Mikuni may be a few millimeters smaller ID, there is also not a butterfly valve like the CVK Keihin uses as a restriction.  So without a flow meter, I would have to guess the maximum flow would be very close to the same.   Anyone with a flow bench and dyno, we need your help..... Fred http://www.arrowheadmotorsports.com   [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Saturday, March 26, 2016 9:15 AM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] [DSN_KLR650] Re: Carb Conversion     I would expect less lag from the Mikuni because there throttle is opened directly. I would expect better low RPM response also, due to the smaller bore carb since air flow velocity is higher but that it will lose out on maximum power for the same reason. Since that's not always the case in practice when comparing different models of carb, I'm interested as to the results.

[Fred Hink]

Yes, there is a throttle cable, throttle, fuel line, hose clamps, fuel filter, extra jets, etc etc. It is a bolt-on kit for the Gen 1 KLRs.  The Gen 2 uses two vacuum lines that will need a tee to make those work that is not included in the kit.   [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Saturday, March 26, 2016 9:29 AM [b]To:[/b] DSN_KLR650@yahoogroups.com ; moabmc@... [b]Subject:[/b] Re: [DSN_KLR650] Re: Carb Conversion     Does the carb kit include a throttle cable or do we use the OEM KLR cable? [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2F2016%2Ficons%2Ficon-envelope-tick-round-orange-v1.png&t=1571810451&sig=_SPzIOC7DsOWzPSs.ZucEQ--~E[/img] Virus-free. www.avast.com   On Fri, Mar 25, 2016 at 1:35 PM, 'Fred Hink' moabmc@... [DSN_KLR650] DSN_KLR650@yahoogroups.com> wrote:

I sold a Mikuni carb kit and an Air/Fuel Ratio Monitor to jettin Jim who said he was going to run his KLR before and after on a dyno.  So far I have not heard any results.  I doubt there is going to be much difference and any difference should be the result of the jetting that has been chosen.  The Mikuni carb s advantage is not in making more total horsepower but the drivability of the bike and having more power down low in the power-band can be felt in your seat of the pants dyno. Fred http://www.arrowheadmotorsports.com   [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Friday, March 25, 2016 12:11 PM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] [DSN_KLR650] Re: Carb Conversion    

Just wanting to close the loop of "I wonder". Has anyone made a quantitative comparison as to maximum power between the two carbs?

 

[Ron Haraseth]

I had contemplated that aspect only to question the amount of reduction of potential air flow was introduced in the CVK by the throttle butterfly valve.  I suspect it a wash, but could imagine the CVK with the butterfly valve actually reduces the air flow, and particularly clean air flow, as compared to the VM.   Another aspect I ve never expressed is the stories I ve heard that the CVK adjusts the mixture to altitude (if only slightly).  I see nothing in the CVK which would alter the mixture based on altitude.  The diaphragm is operated by engine vacuum only.  The slide raises more slowly at altitude perhaps, but that would not alter the mixture at any particular position of the slide and that is the only mechanism which controls mixture and only then altering the mixture based on the position of the slide.   The main advantage to a diaphragm carb is that it will only raise the slide at a rate to match the requirements of the engine based entirely on vacuum.   In my opinion, the simplicity of operation, accessibility to maintain/adjust the carb, and full range tune-ability far outweigh any other advantage the CVK might have.    In the practical sense, however, a mechanical rooky should not attempt the change if they are not already fully familiar with the idiosyncrasies of the CVK and not be willing to manage the conversion and tuning themselves, and should not depend on their local shop to help with any conversion issues.  Most professional motorcycle shop mechanics would freak out when they see a no-standard component.    Ron   [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Saturday, March 26, 2016 9:15 AM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] [DSN_KLR650] Re: Carb Conversion     I would expect less lag from the Mikuni because there throttle is opened directly. I would expect better low RPM response also, due to the smaller bore carb since air flow velocity is higher but that it will lose out on maximum power for the same reason. Since that's not always the case in practice when comparing different models of carb, I'm interested as to the results.

[Fred Hink]

Yes, to all your positive attributes and I would highly recommend that getting rid of the two rubber diaphragms also contribute to a much more reliable fuel mixer.  Rubber and ethanol just don t mix very well.  It s not if they will fail but when.   I am confident that with all the feedback I have received the recommended jets included in the instructions with this kit should satisfy 99% of those using this carburetor.  It really is a pretty easy installation, of course there are those that can t walk and chew gum at the same time.  DOH!   I agree that most bike shops shouldn t be trusted in jetting your bike.  If you can read and follow instructions, it is a much more satisfying job to do it yourself and you may learn something in the process.   Fred http://www.arrowheadmotorsports.com   [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Saturday, March 26, 2016 10:15 AM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] Re: [DSN_KLR650] Re: Carb Conversion     I had contemplated that aspect only to question the amount of reduction of potential air flow was introduced in the CVK by the throttle butterfly valve.  I suspect it a wash, but could imagine the CVK with the butterfly valve actually reduces the air flow, and particularly clean air flow, as compared to the VM.   Another aspect I ve never expressed is the stories I ve heard that the CVK adjusts the mixture to altitude (if only slightly).  I see nothing in the CVK which would alter the mixture based on altitude.  The diaphragm is operated by engine vacuum only.  The slide raises more slowly at altitude perhaps, but that would not alter the mixture at any particular position of the slide and that is the only mechanism which controls mixture and only then altering the mixture based on the position of the slide.   The main advantage to a diaphragm carb is that it will only raise the slide at a rate to match the requirements of the engine based entirely on vacuum.   In my opinion, the simplicity of operation, accessibility to maintain/adjust the carb, and full range tune-ability far outweigh any other advantage the CVK might have.    In the practical sense, however, a mechanical rooky should not attempt the change if they are not already fully familiar with the idiosyncrasies of the CVK and not be willing to manage the conversion and tuning themselves, and should not depend on their local shop to help with any conversion issues.  Most professional motorcycle shop mechanics would freak out when they see a no-standard component.    Ron   [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Saturday, March 26, 2016 9:15 AM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] [DSN_KLR650] Re: Carb Conversion    

I would expect less lag from the Mikuni because there throttle is opened directly. I would expect better low RPM response also, due to the smaller bore carb since air flow velocity is higher but that it will lose out on maximum power for the same reason. Since that's not always the case in practice when comparing different models of carb, I'm interested as to the results.

[achesley43@ymail.com]

Reading the messages on the VM carb swap out reminds me of when I did this to my '82 Yamaha XV920RH.  Two 38mm VM Carbs. Wow, what a difference. Never did take the time to set them up properly for the engine. IE  slide cut, needle, needle jet and other jets. Parts were hard to get back then for conversions and had a trip to Colorado coming up so put the stock stuff back on for that. 

This year I bought my old KLR a new rear shock. Hmmmmmmmm Next year, the VM carb conversion perhaps. 

[hillrallyuk]

There IS a small amount of compensation for altitude in the CVK and similar carbs, because the slide is positioned by the difference between atmospheric pressure and engine vacuum. As you climb a mountain the pressure below the diaphragm becomes lower, so that there is less difference above and below. This means that the slide (and needle) does not lift as far and the rider will give it more throttle to maintain progress. I've done a few trips around the Pyr n es where bikes with standard cable slides would stop for needle adjustment, but those with diaphragm carbs didn't need to do anything.

[Don Dodge]

So far, (the weather has not been cooperative) I am happy with the throttle response of the VM carb. I actually got too much throttle a couple of times in the woods on a single track! The bike runs clean and strong up to 65 mph (5k rpm) One fun thing - it starts more easily than it used to. Thanks for your work, Fred! Don Dodge

On Sat, Mar 26, 2016 at 10:29 AM, Martin Earl mjearl4@... [DSN_KLR650] DSN_KLR650@yahoogroups.com> wrote: [u][/u] Does the carb kit include a throttle cable or do we use the OEM KLR cable? [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2F2016%2Ficons%2Ficon-envelope-tick-round-orange-v1.png&t=1571810452&sig=1Ihe8nTMpcXy5ZxtylaKAw--~E[/img] Virus-free. www.avast.com On Fri, Mar 25, 2016 at 1:35 PM, 'Fred Hink' moabmc@... [DSN_KLR650] DSN_KLR650@yahoogroups.com> wrote: I sold a Mikuni carb kit and an Air/Fuel Ratio Monitor to jettin Jim who said he was going to run his KLR before and after on a dyno. So far I have not heard any results. I doubt there is going to be much difference and any difference should be the result of the jetting that has been chosen. The Mikuni carb s advantage is not in making more total horsepower but the drivability of the bike and having more power down low in the power-band can be felt in your seat of the pants dyno. Fred http://www.arrowheadmotorsports.com [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Friday, March 25, 2016 12:11 PM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] [DSN_KLR650] Re: Carb Conversion Just wanting to close the loop of "I wonder". Has anyone made a quantitative comparison as to maximum power between the two carbs?

[Fred Hink]

I don t get it.  If the slide meters the amount of air to your engine and the needle and needle jet meter the fuel at mid-range and all these are fixed together, how does this change the fuel/air ratio at elevation?   Fred http://www.arrowheadmotorsports.com   [b]From:[/b] DSN_KLR650@yahoogroups.com [b]Sent:[/b] Sunday, March 27, 2016 9:31 AM [b]To:[/b] DSN_KLR650@yahoogroups.com [b]Subject:[/b] [DSN_KLR650] Re: Carb Conversion     There IS a small amount of compensation for altitude in the CVK and similar carbs, because the slide is positioned by the difference between atmospheric pressure and engine vacuum. As you climb a mountain the pressure below the diaphragm becomes lower, so that there is less difference above and below. This means that the slide (and needle) does not lift as far and the rider will give it more throttle to maintain progress. I've done a few trips around the Pyr n es where bikes with standard cable slides would stop for needle adjustment, but those with diaphragm carbs didn't need to do anything.