Transmission style??

[KU_Racing]

This question is for the teams that are using a motor that does not have a transmission built into the casing (a la F4i). What are you guys running for a transmission? Does anyone use a V-twin motorcycle tranny like a 6-speed baker or the OEM equivelent? I am interested in getting away from the F4i if possible, and this is probably one of the biggest problems I have to solve. Thanks!

[rjwoods77]

Use a cvt. Easy solution. Tuning isnt easy to with time you will get it right just like all other things on a car. A-mods use them and they are some of the fastest things around. Check out the vids.
http://www.grmotorsports.com/board/viewtopic.php?t=12736

[Blake_DFSAE]

I've never been to an event but I can imagine how weird a CVT car would sound.

Screaming around the track at a constant 12500 rpm...

[drivetrainUW-Platt]

Why would you want to get rid of a stock integrated transmission. Leave it stock and it wont leak/break/cost a ton.

[mtg]

Originally posted by Rob Woods:
A-mods use them and they are some of the fastest things around.

That's obviously a good reason to use a CVT. Might as well use a wood plank on the bottom of the car also- just like F1.

[Bowtie Man]

mtg, are replies like that really necessary.

A CVT would be a good substitute for a transmission if one is not integrated into the engine. With testing time you can tune the CVT to keep the engine in the power band more effectively.

Luc

[pengulns2001]

KU as in kettering university?

[KU_Racing]

yes, KU as in kettering. i was not saying I want to keep the F4i and get rid of the tranny, I was saying that I want to get rid of the whole f4i assembly and use something else- but other motors I have looked at do not have integrated transmissions, so I have to solve the transmission problem before I present all this to my team. As far as the CVT goes, we have very limited tuning time- i think that puts the CVT out. to be honest, im not a huge CVT fan either. anyone know of a team using a seperate conventional tranny of some kind??

[BeaverGuy]

I'm not sure what engines you are looking at but the motorcycle singles teams are using have integral transmissions. I also second the use of a CVT. Though it may take some time to tune, there are benefits there in both fuel economy and ease of driving. You could also do what Western Washington did with theire V8 car and build your own housing for motorcycle transmission internals in your case using F4I internals.

[Chris Boyden]

Anybody ever seen the MotoGuzzi Convert 2 speed automatic motorcycle....that would be cool to implement with a small lockup converter. No shifting and possibly less fussy than a CVT, but it would be yet another project.

[rjwoods77]

Originally posted by KURacing:
yes, KU as in kettering. i was not saying I want to keep the F4i and get rid of the tranny, I was saying that I want to get rid of the whole f4i assembly and use something else- but other motors I have looked at do not have integrated transmissions, so I have to solve the transmission problem before I present all this to my team. As far as the CVT goes, we have very limited tuning time- i think that puts the CVT out. to be honest, im not a huge CVT fan either. anyone know of a team using a seperate conventional tranny of some kind??

General setup to get running correctly isnt hard at all. Getting the most out of it the hard part. Just geeting the proper engagement speed and backshift characteristics are just read out of a book since they have been so developed over time. I am assuming with over 60hp you would want to use a plorais atv setup (p-90 clutch) that the baja teams use. Hell, you can even get one free from polaris if you ask early enough in the year. If it is any consolation I am using one and will be hammering on it at comp. If it works good then you will already have some decent guidlines to get you started on the next car. The company I am working with is activly looking into the possibility of getting together a package if there is interest.

[KU_Racing]

I would definately be interested in a CVT if i had a source for some setup/tuning datato speed up the process. There is no way, however, that our team would be able to tune a CVT in the amount of testing time that we have (we measure testing time in days, not weeks, and that is if we are done early. If you could give me any CVT information that you have, mr. woods, I would greatly appreciate it. I would of course understand if you dont want to reveal any proprietary secrets or whatever. even any info about this package yur company is working on would be nice.

thanks

[pengulns2001]

i was going there last year, you guys still looking into that 4 cycle dirtbike motor? or something different. yeah tuning time was non existant we went to comp with a car that didnt run last year. hows the car coming?

[Marshall Grice]

Even though i'm not a fan of CVT's, i don't think you could go with a better setup for an engine that doesn't already have an integrated trans.

[rjwoods77]

Originally posted by KURacing:
I would definately be interested in a CVT if i had a source for some setup/tuning datato speed up the process. There is no way, however, that our team would be able to tune a CVT in the amount of testing time that we have (we measure testing time in days, not weeks, and that is if we are done early. If you could give me any CVT information that you have, mr. woods, I would greatly appreciate it. I would of course understand if you dont want to reveal any proprietary secrets or whatever. even any info about this package yur company is working on would be nice.

thanks

Like I said. Youll know how it worked after the comp. No secret or anything. Would be willing to help after I we get it working right. PM me if you are really intersted.

[drivetrainUW-Platt]

what engine are you guys considering that doesnt have a transmission with it, maybe a v-twin Briggs???? That one team ran the 3cyl Mahle engine with the cone type cvt in 04, there car was a tank thou, not sure if they ever ran it, didnt hear any followup after comp.

[rjwoods77]

1: Artic Cat tripple with cvt.

2: polaris 500cc single with p-90 atv cvt.

3: Polaris 600cc twin with p-90 atv cvt.

4: Briggs V-twin with any cvt

The point is look at any cvt driven atv as they usually have a complete setup necessary along with aftermarket parts support.

A bird once told me that weber is considering making a reduced displacement parallel twin for fsae purposes. Same engine that was used in polaris watercraft and now in 4 stroke clean snomobiles. Dry sump, 4 valve/cylinder, balance shafts, CDI.

When you actually look there are a number of different engines in vehicles that the normal formula sae kid wouldnt consider because they arent boy racerish enough that would suit the comp beautifully. I would go with polaris single 500cc with the cvt. So what if it doesnt making shitloads of power. As far as tuning. The one and only god of cvt tuning Mr. Olav Aaen.

http://aaenperformance.com/Power500.asp

http://aaenperformance.com/Acces_P1.asp