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Another alternative that I have been thinking about.

Can a 748R framed 1098RS engine, QS, nemesis t/c, no road gear, no starter motor or starter gear, no reg/rec, no alternator rotor or stator with a lithium batt run on track for around 20 mins sessions?

Can the batt cope with fuel pump and other elec demands?
 

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i saw a baylis 998 at the track operating on a total loss system
 

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I’ve had two total losses! >:)

Craig
The initial total loss is bad and the continuing drain will flatten your battery but you might end up with some smaller drains that are wonderful for about 12 years and then again after about another 6-7 years when they become big drains for another 4 years.
 

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Another alternative that I have been thinking about.

Can a 748R framed 1098RS engine, QS, nemesis t/c, no road gear, no starter motor or starter gear, no reg/rec, no alternator rotor or stator with a lithium batt run on track for around 20 mins sessions?

Can the batt cope with fuel pump and other elec demands?
Yes, this can be done. In 2014 and 2015 we supported a WSBK program that was running total loss, and they were running a significant electronics package.
I personally feel this is not a good idea, but it can certainly be done. Here is my opinion and reasoning, in short: the advantages gained by removing the parts will save you several kg, and will likely increase throttle feel and feedback. You will possibly see 1/2- 1hp on the dyno, and certainly the engine will rev more freely.

Those things may not always be good. Do you want a 1098RS engine to rev more freely? Is that good in a shorter chassis than the 1098? Are you ready to invest is a good set of batteries and chargers? Are you prepared for the increase in maintenance during a race/track day? Ask yourself are there more advantages than disadvantages?

Now, what will you need and how will you determine what to buy?
Id suggest speaking with someone who has direct experience with doing this.

The very first thing you should do is measure actual electrical draw using an ammeter. That would be the best, and only way to really *know* that you can do this.

Or you can guess:
A standard 848/1098/1198 stator puts out around 520 watts (37 amp @14v) *in theory*. In reality, it may put out 10% less, or 33 amp. With street gear replaced by a Nemesis (assuming that is a straight swap in power consumption) you would likely have a few amps of overhead. In other words, Id guess that your electrical needs are somewhere in the area of 26-30 amps continuous.

So, in order for you to be able to run a 20 minute session (including warming up and riding back to your pit) you should plan on 30 min of run time, minimum.

This means that you will need roughly 15 amp hour worth of battery to do this properly, assuming the above assumptions. Here is where it will get tricky.
Most of the lithium battery companies rate their products using *PBEQ* which is supposedly *lead acid equivalent*. It isnt. In my opinion PBEQ is a scam.
What you need to know is *actual amp hour capacity*, and that will need to be at least 15ah. That is going to be a challenge. This may require that you run more than one battery, as building *one*, large enough to do that job will take up a lot of room- which is already at a premium. Note that many MotoGP bikes use multiple batteries due to the demands of the systems.

Note that this will ensure that you *actually* get 30 full minutes of run time.

The above is based on using LFP batteries. If you are willing to run LiPo, you can likely get that capacity with a smaller size battery- but it will also exceed 15-16v. That may not be a problem. Ive had customers being that voltage down to 13.2v in a few ways.

This is much easier with a less expansive electrical system.

Again, my opinion: unless you can find another truly compelling reason to do this, I would avoid it at all costs.
 

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Discussion Starter · #11 ·
Yes, this can be done. In 2014 and 2015 we supported a WSBK program that was running total loss, and they were running a significant electronics package.
I personally feel this is not a good idea, but it can certainly be done. Here is my opinion and reasoning, in short: the advantages gained by removing the parts will save you several kg, and will likely increase throttle feel and feedback. You will possibly see 1/2- 1hp on the dyno, and certainly the engine will rev more freely.

Those things may not always be good. Do you want a 1098RS engine to rev more freely? Is that good in a shorter chassis than the 1098? Are you ready to invest is a good set of batteries and chargers? Are you prepared for the increase in maintenance during a race/track day? Ask yourself are there more advantages than disadvantages?

Now, what will you need and how will you determine what to buy?
Id suggest speaking with someone who has direct experience with doing this.

The very first thing you should do is measure actual electrical draw using an ammeter. That would be the best, and only way to really *know* that you can do this.

Or you can guess:
A standard 848/1098/1198 stator puts out around 520 watts (37 amp @14v) *in theory*. In reality, it may put out 10% less, or 33 amp. With street gear replaced by a Nemesis (assuming that is a straight swap in power consumption) you would likely have a few amps of overhead. In other words, Id guess that your electrical needs are somewhere in the area of 26-30 amps continuous.

So, in order for you to be able to run a 20 minute session (including warming up and riding back to your pit) you should plan on 30 min of run time, minimum.

This means that you will need roughly 15 amp hour worth of battery to do this properly, assuming the above assumptions. Here is where it will get tricky.
Most of the lithium battery companies rate their products using *PBEQ* which is supposedly *lead acid equivalent*. It isnt. In my opinion PBEQ is a scam.
What you need to know is *actual amp hour capacity*, and that will need to be at least 15ah. That is going to be a challenge. This may require that you run more than one battery, as building *one*, large enough to do that job will take up a lot of room- which is already at a premium. Note that many MotoGP bikes use multiple batteries due to the demands of the systems.

Note that this will ensure that you *actually* get 30 full minutes of run time.

The above is based on using LFP batteries. If you are willing to run LiPo, you can likely get that capacity with a smaller size battery- but it will also exceed 15-16v. That may not be a problem. Ive had customers being that voltage down to 13.2v in a few ways.

This is much easier with a less expansive electrical system.

Again, my opinion: unless you can find another truly compelling

Thanks for your answer, I will digest the info. plenty of points raised.

Just for info, the bike has a 1098RS swingarm, linear rocker/TTX, reduced offset yokes/triples, 24 deg steering insert. 46mm Ohlins SBK forks.
 

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Assuming that the cooling fan (5 amps) remains mostly off — your current draw will be fuel pump (5 amps, clean filter), electronic ignition (4 amps), and computer (2 amps), 11 amps total. The stock battery is a Yuasa YTX14-BS (14 amp-hours) so you should have sufficient margin to run total loss for TWO 20 minute sessions.

The problem with this calculation is that the available capacity of a battery is dependent upon the discharge rate, so as the discharge rate increases, the capacity (amp-hours) decreases. Using 11 amps continuously from a 14 amp-hour battery is a hefty discharge rate.

I can tell you that when my 916 charging system failed, I was able to ride to the dealership for a more than 45 minutes (with the headlight disconnected) on a 16 amp-hour OEM battery.
 

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Thanks for your answer, I will digest the info. plenty of points raised.

Just for info, the bike has a 1098RS swingarm, linear rocker/TTX, reduced offset yokes/triples, 24 deg steering insert. 46mm Ohlins SBK forks.
Sounds like a very interesting bike, for sure.

I have a 1098 with RS arm, good geometry, etc, and I cant imaging any reason to convert to total loss- and my engine only makes 160ish HP at the wheel. With the machined/lightened flywheel, it spins really fast. I cant imagine what another 30hp would feel like, especially with no flywheel! Crazy.
 

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Assuming that the cooling fan (5 amps) remains mostly off — your current draw will be fuel pump (5 amps, clean filter), electronic ignition (4 amps), and computer (2 amps), 11 amps total. The stock battery is a Yuasa YTX14-BS (14 amp-hours) so you should have sufficient margin to run total loss for TWO 20 minute sessions.

The problem with this calculation is that the available capacity of a battery is dependent upon the discharge rate, so as the discharge rate increases, the capacity (amp-hours) decreases. Using 11 amps continuously from a 14 amp-hour battery is a hefty discharge rate.

I can tell you that when my 916 charging system failed, I was able to ride to the dealership for a more than 45 minutes (with the headlight disconnected) on a 16 amp-hour OEM battery.
These are good points, but Id like to point out a few things you might have overlooked.

There are a bunch of other components that are going to draw power, including the injectors, coil, dashboard, engine sensors, etc. Assuming that he is using the *R* injectors, that means 4 of them. Then, we move to the Nemesis TC system. Another ECU for that, as well as the sensors. And so on.

As you point out, discharge rate will alter the effective capacity- especially with a lead acid battery. Lead plates will heat up under continuous discharge, leading to increased resistance, and so on.
In your case when your stator failed, you managed to ride for 45 minutes- but Im guessing it was not at full throttle, even assuming that you rode from OB to Kearny Mesa on the 8/52 etc. Point being, as you lean harder on the bike, the pump, injectors, and ECU all draw more current. Since this application is race/trackday, we need to assume max consumption, and plan accordingly.
Lead acid also charges relatively slowly, is bulky, and heavy. Not a big deal for a commuter, but definitely a big deal for a track bike with an RS engine and chassis.

Back to discharge affecting capacity- This is not the same case with lithium as with lead acid- at the rates that we will see here. A properly sized and constructed 16-18ah battery will actually provide 16-18ah with a 20 amp continuous draw. As I pointed out, we always recommend some overhead to account for capacity loss to resistance, and so on. We test these things in our lab, and on the dyno regularly, and this is what we find.
YMMV
 

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Will the lithium batteries hold up to this?
 

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Will the lithium batteries hold up to this?
Yes, lithium batteries are in fact well suited to this sort of use case...provided the battery has a sufficient BMS to control discharge and balancing.

The main point to consider, in my opinion, is that it simply isnt necessary to run total loss- the drawbacks outweigh the benefits, as I outlined in detail upthread.
 

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I was just wondering how the lithium batteries took multiple recharges during the course of a day at the track.


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I was just wondering how the lithium batteries took multiple recharges during the course of a day at the track.
A lot easier and better than lead acid ones do.
Recharge times are really short.
 
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Yes, lithium batteries are in fact well suited to this sort of use case...provided the battery has a sufficient BMS to control discharge and balancing.

The main point to consider, in my opinion, is that it simply isnt necessary to run total loss- the drawbacks outweigh the benefits, as I outlined in detail upthread.
Point is the OP was asking could it work... not if we think he should do it or not.
 
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