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 Post subject: Club Build - Engine
PostPosted: Fri Apr 24, 2009 5:42 pm 
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Let's get this build rolling by starting with the motor. Since we chose to build a "modded stock" bike, we'll need to discuss how "modded" we want the engine to be.

Gus... please give us an inventory of what you already have for motor parts (I'm thinking you probably have a couple of cranks laying around? :D )

After we know what Gus has, post up what you have to donate to help complete the parts list. I will keep a running tab of whose donating what, so we can keep track of the parts sourcing progress.

Hybrid and Jackson.40 have agreed to be our parts-staging liasons for the Far East and the EU respectively. You will ship your donated parts to them and they will coordinate with Gus from there. Those of us in the U.S. and Canada can just ship direct to Gus.

I will post the 3 shipping addresses here when we're ready to begin the parts flow.... :cool:


Last edited by rztom on Fri Apr 24, 2009 5:51 pm, edited 1 time in total.

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PostPosted: Fri Apr 24, 2009 5:44 pm 
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OK... so let's begin our discussion on the engine. I think it should stay a 500cc motor - true to the orginal GP machines of the day. I also think, to keep costs down, it should stay mostly stock. But... of course it'll need a little "massaging" to liven it up a bit.... :twisted:

Remember - we're not building a "monster"... so we should keep these mods reasonable. Let's start with these....

How do we port it?
1) Stock, with a clean-up
2) TSI
3) ??
("porting" will refer to all things intake - reeds, cylinder ports, heads, pistons, etc)

Carbs
- modified stock, 28mm flat slides, or ??
- Stock airbox, filters on elephant ears, open filters or ??

Do we incorporate some of the cooling mods that have been discussed around here lately? Larger radiator? Or leave it stock?

Stock or aftermarket clutch components?

Undercut transmission? Or no?

Re-keyed ignition pickup, or TSI-spec mod?

Aftermarket CDI & YPVS controllers, or stock?

For good streetability, the engine should retain the stock Autolube system.

Take each of these points and give us your feedback. And feel free to add-in anything else I may have missed... :cool:


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PostPosted: Fri Apr 24, 2009 10:03 pm 
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Tom, sorry just noticed the post, on parts I am hurtin for trans bearings that I know, but tomorrow when I get to the shop I will take the time and see how many cylinders I have, how many clutch assy's and everything else, check back then........


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PostPosted: Fri Apr 24, 2009 11:34 pm 
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Gus... do you have a complete transmission? I know you're trying to work out the bearing issues, but other than that, do you have all the shafts, gears, forks, etc?

I was thinking that the tranny would be one of the most difficult assemblies to get all together... :shock:


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PostPosted: Fri Apr 24, 2009 11:44 pm 
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As I was re-reading my post above, I realized that I didn't mention pipes.... :shock:

Pretty important aspect of the whole build, not only in engine performance, but also in fit with the finished frame/bodywork....

I think "GP" style is out of the question (without a banana swinger), so what should we do?... :smt102


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PostPosted: Sat Apr 25, 2009 12:29 am 
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I have a few its the bearings


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PostPosted: Sun Apr 26, 2009 9:27 am 
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well what an interesting day yesterday was got to the shop and I think I actually witnessed a hurricane , tornado something I wasn't there 10 minutes and the power lines were laying on the ground just snapping the poles off pretty wild, so I will head back today and try and see whats what if I have power, I have a complete tranny and I'm sure the forks, and as far as bearings I have some only no new ones, the ones I have may be ok, when Steve says they are NLA I check to see what I have or can get made.


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PostPosted: Sun Apr 26, 2009 9:31 am 
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on pipes this something I always wanted to do, drum roll please, a 2 into 1 :shock: they will have torque and will be different from any others other than 1 of mine!


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PostPosted: Sun Apr 26, 2009 10:05 am 
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Gee Gus I don't know about that. I've seen a few over the years, Kawaski 3
into one. Doesn't seen natural for a 2 stroke. Just my thoughts.


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PostPosted: Sun Apr 26, 2009 12:48 pm 
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snowmobiles that are 2 stroke twins usually have 2into 1's it would be more for torque


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PostPosted: Sun Apr 26, 2009 5:37 pm 
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I know that they work but just seems so differrent.


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PostPosted: Mon Apr 27, 2009 10:36 am 
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I vote we stay with an original 4-pipe layout here. Not sure we really want to go down the "experimental" road with this build.... :cool:


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PostPosted: Mon Apr 27, 2009 10:40 am 
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Gone kinda silent in here.... :shock: Anybody have any feedback on the engine build??


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PostPosted: Mon Apr 27, 2009 12:23 pm 
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I vote for 4 pipes. The smaller the cylinders a snowmobile has the more likely it is to have one pipe per cylinder. Just look at the triples from the late 90's (formula III, mach Z).

I think the undercut tranny and aftermarket ignition is a waste of time and money for this project. Just my 2 cents. I haven't used either of them.

I can throw in an offset key for rear crank timing (assuming I can find it). I believe it's 2.5 degrees. I'm also running 3 barnet clutch springs and 3 stockers. If you choose to go this route I could throw in my other 3 barnett springs.


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PostPosted: Mon Apr 27, 2009 1:56 pm 
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ok 4 pipes it is, when I threw that out there my thought was the club bike should be different, :cool: something that doesn't seem right, :shock:


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