Brammo Owners Forum

General => Off Topic => Topic started by: Richard230 on February 20, 2015, 06:02:50 PM

Title: EV transmissions
Post by: Richard230 on February 20, 2015, 06:02:50 PM
According to a the following statement on page 22 of the March issue of Popular Science, electric vehicles (not necessarily motorcycles) may have a transmission in their future.  Here is the statement:

Single-speed EV transmissions will give way to two-speed units within 5 to 6 years, according to German supplier ZF.  As with gas powered cars, adding more gears to electric motors will make them more efficient, extending their range by up to 20 percent.

Note that ZF makes transmission for many brands of automobiles and has done so for years. I believe that they also make (or used to make) transmissions for some motorcycle brands, such as BMW. 
Title: Re: EV transmissions
Post by: RickXB on February 20, 2015, 06:48:04 PM
maybe some peoples will figure out that a transmission is maybe not REQUIRED but not USELESS either ;)
Title: EV transmissions
Post by: benswing on February 20, 2015, 08:26:17 PM
Tesla tried a 2-speed transmission with their roadster.  It failed and they never looked back.  Now they have the quickest production electric car with the longest range. 

Unsurprising that a transmission company would think they are a good idea putting them where they aren't needed.


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Title: EV transmissions
Post by: 7racer on February 22, 2015, 12:54:27 PM

Tesla tried a 2-speed transmission with their roadster.  It failed and they never looked back.  Now they have the quickest production electric car with the longest range. 

Unsurprising that a transmission company would think they are a good idea putting them where they aren't needed.


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True. I own both a Teslas and the Brammo. I love the simplicity of the Teslas with one gear BUT for performance imthe tesla really needs an extra gear. It is really evident when you watch the drag videos as the Model S blows by everything off the line but runs out of steam and gets reeled in.

About distance, I'm not sure. If a 20% increase in range is possible the. I think they will move rapidly to it.

I am hoping they do it more for performance. Taking the Tesla (roadster) out on the track you can easily see it get winded j. The straights.

Title: Re: EV transmissions
Post by: MichaelJ on February 22, 2015, 02:57:25 PM
The LITO Sora has a CVT.  A CVT doesn't offer discrete gears, but is not a one-speed, either.  If transmissions don't make sense for a modern EV, then why is LITO Green Motion betting their customers will spend a pretty penny on it?

I have a vehicle with a CD player.  It happens to be an EV: a Nissan LEAF.  It also has Bluetooth and a USB port for supplying the music player with content.  Arguably, the CD player is not needed.  But it's there.  For those who still use physical media, the CD player is useful.

I enjoy my Empulse R, gearbox and all.  The gearbox is useful for on-the-fly adjustments of regenerative braking power on the hills in my area as described by Shinysideup (http://brammoforum.com/index.php?topic=2734.0).  The Zero can't do this on the fly, but I'm not going to rain on Zero's parade because of it.  Instead, I'll tease it about its ongoing lack of reliable DC fast charging.  :)


I appreciate having experienced (and continuing to experience) operating an e-motorcycle with a gearbox.  It is not a bad experience, and if transmissions disappear from all EVs in the future, I won't whine about it.
Title: Re: EV transmissions
Post by: 00049 (AKA SopFu) on February 22, 2015, 09:08:03 PM
It seems to me that transmissions only add a significant benefit when the vehicle is operated near it's maximum potential. Like on a race track (formulaE), or moving heavy loads (electric garbage trucks, dock trucks, etc), or when the powertrain is simply under-powered relative to the expectations of performance (electric kei cars).

As Tesla has shown, with enough power, a transmission is not needed.
Title: Re: EV transmissions
Post by: BrammoBrian on February 22, 2015, 11:59:22 PM
I think the question we have to ponder before you answer this question is... "What is ENOUGH performance?".  The Tesla is certainly quick in a sprint from 0-60mph, but it's not going to win a race against a real sportscar around a track or for anything more than a 1/4 mile drag.  This is still more than ENOUGH performance for most people, even though it is possible to have more.  The truth is that IF the Tesla had a transmission, the performance would be even more impressive.  The 0-60 time might not improve much due to adhesion limits of tires, but the top speed could certainly be increased.  So... it's not that the transmission was "useless", just that Tesla determined they could meet the minimum performance expectation for the majority of their customers (ENOUGH) to be happy without including the additional cost. This is smart value engineering and great customer centric design decision making, not ultimately a technical decision of what is “best”.

With motorcycles, I think it is even more subjective.  I have ridden many, many direct drive motorcycles in my career including the Mission R, Vectrix Maxi-Scooter, KTM Freeride, 2014 Zero S, 2011 Zero X, and our own Enertia, Empulse prototype, and Empulse RR race bike.  In some cases, the performance was ENOUGH, and others it was not.

I agree that for the most part - the buying public is leaning towards a compromise of ease of use over outright performance in EV.  I am hopeful that there will still be those among us that continue to push for performance though as we show the way for what is possible.   This is one of the reasons I have built the Empulse HVR (see News thread) to combine a high voltage drivetrain with a six-speed transmission.  If it was pointless on the 104Vdc street-bike, it must be doubly-so on a 325Vdc race bike, right?  As you could guess – I am not finding that the best performance comes from leaving the bike in one gear, however.

The transmission is simply a way to multiply torque to the rear wheel and provide a rider with an additional tool (clutch and gear ratios) to use.  If you're not particularly fond of, or good at, using a manual transmission on a gas bike or car, you'll probably not prefer it on an EV either. And even if you are, you might still decide that it's got no place on an EV as direct drive is ENOUGH.  It's nice to have the choice. 
Title: Re: EV transmissions
Post by: Shinysideup on February 23, 2015, 01:14:26 AM
Thanks for your interesting insights. Yeah, for some of us, "enough" is not enough!

BTW, I can find no trace of the Empulse HVR, either on this forum, on brammo.com, or on the Brammo FB page. Even Google couldn't find it. Did you spill some beans? ;)
Title: Re: EV transmissions
Post by: roma258 on February 23, 2015, 10:34:29 AM
Seriously, spill a few more beans on the Empulse HVR please!

I think the fact that the the eMoto series is pretty much a single-model series for 2 years running does validate the gearbox approach to some degree. Now how that translates to the street is another question, but if there was no advantage to be gained, why isn't anyone fielding the Zero SR with its more powerful motor? The chassis can't be that much worse, can it?
Title: Re: EV transmissions
Post by: Richard230 on February 23, 2015, 10:55:09 AM
I tend to look at electric motorcycles from a future consumer standpoint - where sales count the most.  I believe that not having a clutch and transmission on an electric motorcycle is the best approach to marketing them to new riders and expanding the customer base in the future.  Just compare the sales of manual transmission vehicles to automatic vehicles to show where customers are going. 

Now if someone made a CVT or some other sort of automatic transmission motorcycle, that would accomplish the same thing, that would work too.  But with electric motors, what would be the point, especially for an entry-level vehicle?  Right now younger people are not buying motorcycles and staying in the sport the way they used to.  I think the ease of riding, reduced impact on the environment, quiet and smooth operation, lack of much maintenance, reduced running costs and various other benefits will gradually increase the sales and popularity of electric motorcycles. But these benefits will take time to be appreciated.

While transmissions have a mechanical value, I think the lack of one will increase sales to new riders and that is where the future lies.  All that really needs to be done is to find some way to lower the purchase price and to have the major manufacturers get into the market (such as Polaris will be doing).

When I go  to BMW rallies, you would be hard pressed to find anyone under the age of 50 or 60.  That is not the future.  The future will be young people buying and riding electric vehicles - but it is just going to take some time and no one will be getting rich for a while (which is a real issue for a investor-driven company).

I am really going to be interested in seeing what Polaris does during the next few years with electric motorcycles.  Unfortunately (from my point of view), my guess is that they will go high-end, as they have with their other motorcycle brands, and this will limit any hope for volume sales.  Whatever happens the future should be very interesting for us early electric motorcycle enthusiasts.
Title: Re: EV transmissions
Post by: Ted Dillard on February 23, 2015, 12:32:27 PM
BTW, I can find no trace of the Empulse HVR, either on this forum, on brammo.com, or on the Brammo FB page. Even Google couldn't find it. Did you spill some beans? ;)

It was in the thread that you commented on yesterday, responding to my question to Brian: http://brammoforum.com/index.php?topic=2877.0 (http://brammoforum.com/index.php?topic=2877.0)

The LITO Sora has a CVT.  A CVT doesn't offer discrete gears, but is not a one-speed, either.  If transmissions don't make sense for a modern EV, then why is LITO Green Motion betting their customers will spend a pretty penny on it?

Why indeed?  There are a lot of things on the Lito that are interesting, and unnecessary.  For their target market of "luxury EV buyers", it may be a good fit, though - time will tell.  Simply using their example to justify a CVT doesn't really hold water, though.  I can point to several instances of a CVT that have been dumped for EV use. 

I think the question we have to ponder before you answer this question is... "What is ENOUGH performance?".

I don't think this argument holds water either, now that we can see numbers from bikes like the Energica, the Mission, performance like the racing of the '14 Zero SR, your bikes, and a field of gas bikes.  The only argument that makes any sense to me at all is that of the choice being for the "rider experience".   Unless I missed something, when you compare performance between similar bikes with, and without a transmission it's a wash at best. 

Here's some reference: https://evmc2.wordpress.com/2013/04/27/transmission-questions-finally-answered-zero-brammo-comparison/ (https://evmc2.wordpress.com/2013/04/27/transmission-questions-finally-answered-zero-brammo-comparison/)

Here's another post re the Laguna Seca results ca. 2013: https://evmc2.wordpress.com/2013/07/21/transmission-debate-qualifying-results-at-laguna-seca-fim-err/ (https://evmc2.wordpress.com/2013/07/21/transmission-debate-qualifying-results-at-laguna-seca-fim-err/)

As with anything else in engineering and Physics, you can get to the same place any number of ways.  I have no problem with Brammo using a transmission, though I think the general consensus is that 6 speeds is more a function of what was available than what was best.  And I have no issue with riders wanting a transmission because they simply like it better. 

I don't, however, feel like anyone can point to one design or another and say it will give you better performance, and I'd truly welcome an education on it if I'm wrong.  As long as it doesn't include the phrase "torque multiplying"  ::)
Title: Re: EV transmissions
Post by: RickXB on February 23, 2015, 03:04:51 PM
I think for a given motor, multiple ratio will be superior over single ratio. Is it the only solution to increase performance? No . Since everything is a compromise between cost, time, weigth, volume, reliability etc.
they choose to go with the tranny because delivering a single ratio bike that doesn't meet performance expectation was not a option. HV was not an option either unless delivering 1 bike a month for 30k+$ is what you call a production bike. And finally it' not because tesla is not doing it that mean it's the only one solution. The 60-120mph is a tad sluggish for the asking price & probably my old IROC 86 350sbc have a better 60-120mph but nothing close to their 0-60. that's what i call compromise. Their is so few EV manufacturer that I don't think one company can say they found the perfect way to design an EV.
Title: Re: EV transmissions
Post by: benswing on February 23, 2015, 03:07:26 PM
The truth is that IF the Tesla had a transmission, the performance would be even more impressive.  The 0-60 time might not improve much due to adhesion limits of tires, but the top speed could certainly be increased.  So... it's not that the transmission was "useless", just that Tesla determined they could meet the minimum performance expectation for the majority of their customers (ENOUGH) to be happy without including the additional cost.

Also it was unreliable and kept breaking down. 

I agree that for the most part - the buying public is leaning towards a compromise of ease of use over outright performance in EV.  I am hopeful that there will still be those among us that continue to push for performance though as we show the way for what is possible.   

This seems to be the consensus in our little unplanned poll.  Most of the supporters of single-gear have been making the point that they get plenty of power for all their needs from EV's with a single gear.  The supporters of transmissions have been pointing to racing or squeezing out a bit more power in the lowest gear. 

There are costs and benefits to both, everybody does their own calculus to determine what fits their wants and needs. 

Thanks for your insight, Brian!
Title: Re: EV transmissions
Post by: RickXB on February 23, 2015, 03:51:09 PM
agree but when you cash out 15500$cad for a ZF9 , 17700$ for a ZF12 or 20000$ for a SR, I expect a bit more than a commuter. That kind of money is way north for a newcomer.16k for the Empulse R vs 20k for the SR, it was a no brainer to me. If you say same bike/same perfomance/same price but without a tranny, i will go without it but otherwise i'll stick with the shift
Title: Re: EV transmissions
Post by: benswing on February 23, 2015, 04:08:19 PM
16k for the Empulse R vs 20k for the SR

That must have been the fire sale.  Regular pricing for the SR was $1,000 less than an Empulse R.
Title: Re: EV transmissions
Post by: RickXB on February 23, 2015, 04:21:29 PM
[That must have been the fire sale.  Regular pricing for the SR was $1,000 less than an Empulse R.

yep, without that price, i wouldn't be a EV rider :-[
Title: Re: EV transmissions
Post by: Ted Dillard on February 23, 2015, 04:42:41 PM
By the way if you're interested, and hopefully not too far off-topic, but Biff (a guy active on both elmoto and ES) did a great couple of posts on high vs low voltage, and kindly let me republish them here:

explanation: https://evmc2.wordpress.com/2015/02/10/voltage-high-or-low-explained/
the math: https://evmc2.wordpress.com/2015/02/12/voltage-high-or-low-the-maths/

Bottom line is it's more about the parts and pieces, and what makes a practical build than anything else, at least that's what I got from it.  For example, for my CBR600RR build, I want 100kW, and the Emrax 268 with the Rinehart controller wants to play at just shy of 400V.  The amps are less, so the cabling and connecting is less money, size and weight.  Of course, builder/user safety is a big concern too.

But it's all hinging on my motor choice.  (100kW @ 45lbs.)  The efficiency and power between the two all come out in the wash.

That build plan is here: https://evmc2.wordpress.com/2014/12/20/shopping-list-superbike-check/
...and no transmissh.   ::)
Title: Re: EV transmissions
Post by: protomech on February 23, 2015, 10:45:27 PM
Interesting that both Biff and Luke have spoken recently about HV (300+V) systems against LV (~100V) systems.

Biff mentions the difficulty of quick-charging at low voltage, but I think he misstates the importance of the network effect.

Who would start selling a LV electric car that essentially trickle charges on 200A QC stations? A 50 kWh LV car would charge at only 20 kW (2.5h) from a "100 kW" QC station.

Who would start selling or retrofitting QC stations to support these LV cars? The cablesets and connectors would need to be redesigned, all of the power electronics inside the charger would need to be replaced. More expensive than simply adapting an existing design for multi-standard CHAdeMO + J1772 combo. Even at "moderate" QC power levels like 100 kW, a 20 ft 1000A cableset and connector will weigh around 100 pounds .. and be worth about $150 in scrap value just for the copper. Hope the charging park is well-lit ..
Title: Re: EV transmissions
Post by: flar on February 24, 2015, 09:28:22 PM
For my own part of the debate - I tried a 2012 Zero S and it wasn't enough to wow me, but it was enough for me to consider EV bikes.  The promise of the Empulse sounded more like what I was looking for and when I finally tried it, the performance matched what I wanted for a street bike/commuter with a wow factor.  I also tried the 2013 Zero S that had the newly designed motor before I pulled the trigger and my impression was that if it had been available a year earlier I wouldn't have bothered waiting, but it wasn't and since the Empulse offered a higher acceleration wow factor at the same time (actually a month or so earlier), I was happy to go with it.  Note that at the time I did note that their roll-on performance at speed felt very similar, but the 2013 S still did not have the urgency from a stop light that I like.  I've never ridden the SR so I'm a bit curious about that, but I've already made my EV bike purchase for the near future so I don't necessarily want to know. ;)

WRT the transmission being a handicap in the process of cornering - if I was racing it then it might be more of a factor, but for my back-road mountain riding it's not an obstacle because I don't row the gears for every corner.  I pick a gear for a stretch of road and stay in it.  In that respect the Empulse is more like an on-the-fly tunable single gear bike in terms of how much effort I expend.  The number of gears works well for that since the different parts of Skyline may cause me to choose any of up to 3 different gears for a minute or two at a time and for a fairly small total range of speeds (i.e. some parts might average 50, some 60, but it's not like I'm doing 20 here and 90 there).  With only a couple of gears I would find maybe only 1 gear that worked for an entire run.  I suppose the transmission could have just the 3 or so gears I use on Skyline, but that would be purpose built for that one situation and we have 6 speed gear sets already available.  I also take into consideration that I already have a familiarity with how much of a difference a single gear shift makes when choosing gears from among 6.  I'm coming up to a really satisfying set of curves on Skyline on the Empulse and I already know just how many clicks to make so that the next 5 corners work very well.  I would have to spend a few months learning a whole new set of gear intervals if they had provided a 2 or 3 gear transmission.

I've seen a number of reviews of the Empulse where the transmission was docked for a lot of reasons that you can train out of yourself in just a couple of rides if you talk to the right people.  The most obvious is "don't pull in the clutch at a stop light" and I've seen comments in reviews that made me wonder if the riders had at least been reminded of that given the comments they were making.  There were also comments about the clunk from a stop which is eliminated using the 2 inch rollback technique that I first remember Shinysideup describing here.  Matching revs and the motor whining is also an indication that they didn't try power shifting which works amazingly well on this bike.  With a proper 1 minute discussion before a test ride, the impression of the transmission on this bike can dramatically improve.  This, of course, goes against the standard marketing comment that the transmission is there for familiarity (well, to a point, and it is possible to get where you are going without being aware of any differences to be sure - but for ... sake, go over a few points for maximum enjoyment, no?).
Title: Re: EV transmissions
Post by: flar on February 24, 2015, 09:47:41 PM
One question for the people who understand electric motors and controllers here.  I know that the Tesla can pretty much be driven with a single pedal, using generous regen to slow the car down.  The same can be done with the Empulse, but you definitely need to shift down to 1st for some intersections to get it nearly stopped as some of the higher gears don't quite provide the same "I'll get you nearly stopped" response.  The regen can also be modified by choosing Sport or Normal mode so it is somewhat under the control of the electronics as well (and can't the Zeros tune this with their phone app?).

My question would be - would high voltage systems be more capable of providing more regen braking (and tunable/selectable engine braking like you get with your pedal position on a Tesla) even with a single tall gear?

(And there is still that issue that someone claimed that Vectrix had patented the concept of selectable regen through reverse handlebar twists - is that true, and is that still true now that they've been liquidated?)
Title: Re: EV transmissions
Post by: BrammoBrian on February 24, 2015, 11:54:47 PM

I think the question we have to ponder before you answer this question is... "What is ENOUGH performance?".

I don't think this argument holds water either, now that we can see numbers from bikes like the Energica, the Mission, performance like the racing of the '14 Zero SR, your bikes, and a field of gas bikes.  The only argument that makes any sense to me at all is that of the choice being for the "rider experience".   Unless I missed something, when you compare performance between similar bikes with, and without a transmission it's a wash at best. 

Here's some reference: https://evmc2.wordpress.com/2013/04/27/transmission-questions-finally-answered-zero-brammo-comparison/ (https://evmc2.wordpress.com/2013/04/27/transmission-questions-finally-answered-zero-brammo-comparison/)

Here's another post re the Laguna Seca results ca. 2013: https://evmc2.wordpress.com/2013/07/21/transmission-debate-qualifying-results-at-laguna-seca-fim-err/ (https://evmc2.wordpress.com/2013/07/21/transmission-debate-qualifying-results-at-laguna-seca-fim-err/)

As with anything else in engineering and Physics, you can get to the same place any number of ways.  I have no problem with Brammo using a transmission, though I think the general consensus is that 6 speeds is more a function of what was available than what was best.  And I have no issue with riders wanting a transmission because they simply like it better. 

I don't, however, feel like anyone can point to one design or another and say it will give you better performance, and I'd truly welcome an education on it if I'm wrong.  As long as it doesn't include the phrase "torque multiplying"  ::)

You might have missed the re-match between the TTX and Kenyon's Zero S race bike...

In the same 2013 season, Kenyon came out to race in the final AFM race of the season with the same Zero S that he placed 2nd on at Laguna Seca.  This time, we put Eric Bostrom on the bike.  The result was that Eric finished a six lap race ahead of Kenyon by about 20 seconds.  :o 

https://www.brammo.com/blogs/?p=1916 (https://www.brammo.com/blogs/?p=1916)

(http://www.brammo.com/blogs/wp-content/uploads/2013/10/4.png)

Then... in 2014, we gave the TTX to Eric for the ReFuel event at Laguna Seca, where he bested the Zero qualifying lap record by over 2 seconds on his single, flying lap.  He was also faster than Jeremiah Johnson's modified Zero, the fastest of the rest, by over 6 seconds on the day.   

https://www.brammo.com/blogs/?p=1946 (https://www.brammo.com/blogs/?p=1946)

Do I think that this settles things - No, of course not.  I just want to highlight the difference a rider makes in maximizing the available performance from any motorcycle.  Eric, a professional rider, was able to use the transmission to full advantage. 

Here are the primary benefits over direct-drive (which I am also not against as a solution):

1. You can use a physically smaller motor as you require less torque from your motor.  This may equate to more efficient packaging of your battery, if done properly.  It theoretically makes the motor magnetics less expensive as well.
2. Clutch can be used to disengage the driveline in an emergency.
3. Final drive gearing is less critical with a multi-speed transmission as the rider can select different ratios.
4. Maximize acceleration and top speed. Less compromise.
5. Allows for variable regen through the gears as Flar has mentioned.
6. Since you cant' stall and the motor has torque from 0 rpm, you can choose not to shift. IF you're feeling lazy, put her in third and ride it like a scooter.

Here are the downsides:

1. Adds some weight (although your motor is smaller and lighter) and complexity.
2. Increases the driveline harshness with more moving parts and resulting mechanical tolerance (slop).
3. Requires more rider training and skill to master.
4. Adds cost to an already expensive product. 
5. Having to explain the difference between motor torque and rear wheel torque by using the term "torque multiplication" over and over...  ;)
Title: Re: EV transmissions
Post by: skuzzle on February 25, 2015, 01:41:50 AM
Any thoughts on why a wet clutch is used for the Empulse?  With the electric motor there is no engine by-products to deal with.  It seems like a dry clutch would allow the best gear oil to be used.  The oil change interval would probably go from 3000 miles to probably over 20000.
Title: Re: EV transmissions
Post by: Chocula on February 25, 2015, 02:03:47 AM
That is the best looking Zero I have seen yet.  I also love the look of the "half" fairing on the Brammo and would love to see that be made available in a street legal configuration for my Brammo.

This has been a great discussion and while I agree with Ted that with a big enough motor and controller, a transmission is not needed.  Unfortunately, until a bike is available that I can afford which is traction limited up to about 80 mph with a top end of at least 150, a transmission will still offer some advantages.

It took a few weeks of riding to get used to riding smoothly on the Brammo, but like everything else, you get better with more experience.  The drive train lash is just as bad on my ICE bike, its just that everything else is rattling so much you don't notice,  the clutch on my ICE bike is way smoother, and its engine does not have nearly the instant torque like the Brammo.

I can also see value of a transmission in racing once electrics become popular enough to separate them into classes based on motor and controller size.
Title: Re: EV transmissions
Post by: Ted Dillard on February 25, 2015, 06:33:10 AM
Thanks Brian.  On the riders, I've had long conversations with Rob Barber who rode the Ohio State IOM bike to third last year, about transmissions, riding style, riding strategy, use of regen, etc and how it's different than gas bikes with transmissions - admittedly not electric bikes with transmissions - and he likes it.  :D  I've talked to a few other pro riders as well over the years.  I think that, bottom line, they all are still learning about the EV drivetrain and how to ride it - tranny or no. Think what Kenny Roberts did for riding style in what, the early '70s? 

Barber, interestingly, runs the bike with little or no regen, and prefers controlling his front-to-back braking himself.  He also feels that the rider control is more "pure" and allows better entrance and exit to curves once the rider understands the timing.   etc etc. 

For me, personally, the lack of transmission on an insanely powerful bike is precisely what I love about electric motorcycles.  Beginning and end of story.  See this: http://insideevs.com/electric-motorcycle-primer-insideevs-style-part-1-ride/ (http://insideevs.com/electric-motorcycle-primer-insideevs-style-part-1-ride/)

And not to be a bitch, but I don't consider either the Empulse or the Zero SR to be "insanely powerful".   ::)

"Do I think that this settles things - No, of course not."  If there was information, performance and data that supported a transmission as clearly better for performance, that would be one thing.  The fact that the two bikes are closely matched serves to make my point.  But to toss the EV ride experience "baby" with the transmission ideology bathwater, it's not my choice. 

And as I've said before, it would be a shame if the folks who like shifting didn't have that option.

And, I do have to crack up at your mention of cost.  Somewhere else - I think it a comment thread on IEV maybe, I got beat up because they claimed Brammo claims one of the reasons they use a tranny is the "cost factor".  Something I hadn't heard before.   :o  I think they even attributed the claim to you lol.