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Author Topic: What class would a bike with this engine run in?  (Read 8147 times)

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Offline Briz

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What class would a bike with this engine run in?
« on: September 15, 2010, 03:11:56 PM »
I'm pretty new & fairly clueless as regards motorcycle classes, bear with me...
I'm very tempted to go for a deal on a very rare Weslake DOHC V-twin:



Production numbers are vague, but no more than 20 were made (they made many more pushrod versions)
Capacity is 1000cc
The thing is; what class would I end up running in? It'd be running on gas and the bike would be a basic unfaired configuration.
While I'd be doing it more for the experience than to set records, it'd be good to think there was some kind of attainable target to aim for!

Offline Nortonist 592

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Re: What class would a bike with this engine run in?
« Reply #1 on: September 15, 2010, 03:21:48 PM »
The simple answer is whatever you build (solo or sidecar) you would be in A.  And as a Weslake lover I am really jealous!!  Nice find.  Hope you snap it up.
Get off the stove Grandad.  You're too old to be riding the range.

Offline nrhs sales

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Re: What class would a bike with this engine run in?
« Reply #2 on: September 15, 2010, 03:29:42 PM »
How old is it? Might be able to run vintage class?

Offline Nortonist 592

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Re: What class would a bike with this engine run in?
« Reply #3 on: September 15, 2010, 03:32:03 PM »
How old is it? Might be able to run vintage class?

Not old enogh for vintage.  But it would look absolutely fantastic in a wideline!!!
Get off the stove Grandad.  You're too old to be riding the range.

Offline nrhs sales

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Re: What class would a bike with this engine run in?
« Reply #4 on: September 15, 2010, 03:35:44 PM »
So if it is not old enough for vintage and it does not use pushrods that would put it in the same class as a new 1000cc GSXR or CBR engine.   Hope it makes at least 150 hp!!!   :evil:

Offline Nortonist 592

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Re: What class would a bike with this engine run in?
« Reply #5 on: September 15, 2010, 04:16:22 PM »
Thats the unfortunate part of these wonderful engines.  But it should, with decent aero, be able to run 150.  My 500cc pushrod Weslake ran 125.715 at SpeedWeek this year so 150 from a DOHC 4 valve Vee twin shouldn't be a problem.
Get off the stove Grandad.  You're too old to be riding the range.

Offline nrhs sales

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Re: What class would a bike with this engine run in?
« Reply #6 on: September 15, 2010, 04:18:20 PM »
150 hp not 150 mph.

Offline Nortonist 592

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Re: What class would a bike with this engine run in?
« Reply #7 on: September 15, 2010, 04:29:35 PM »
Apologies!   I have a very short attention span.  150hp would be attainable on fuel.  Not sure about gas.  Probably around 120 hp.
Get off the stove Grandad.  You're too old to be riding the range.

Offline Briz

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Re: What class would a bike with this engine run in?
« Reply #8 on: September 15, 2010, 04:51:39 PM »
So if it is not old enough for vintage and it does not use pushrods that would put it in the same class as a new 1000cc GSXR or CBR engine.   Hope it makes at least 150 hp!!!   :evil:

Thanks for the replys guys.
This is what I was afraid of!  Its rated at 100hp as it is and 120 is said to be fairly easily attainable. The current owner checked compression and reckons it has less than 9:1 so theres some scope for improvement right there. Whats the deal with running race gas? does that bump things into higher classes? How about a blower or a turbo? its likely that this engine is built tough, but clearly any hop-up parts would need to be custom made.
Beginning to sound like I'd be better off with a pushrod motor!

Offline nrhs sales

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Re: What class would a bike with this engine run in?
« Reply #9 on: September 15, 2010, 04:54:55 PM »
The good news is race gas does not change your class as long as you buy the approved race gas at the event from ERC.  He stocks gas anywhere from around 101 octane up to something like 118 octane so you should have no worries there.  Blowers and Turbos would put you in the boosted class which often times has slower records than the normally aspirated classes believe it or not.

Offline RichFox

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Re: What class would a bike with this engine run in?
« Reply #10 on: September 15, 2010, 05:11:13 PM »
I don't do or understand bikes but a quick glance at the rule book looks like depending on faring and whatnot that I don't understand your looking at records between 175 and 230. Isn't that about right?

Offline 55chevr

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Re: What class would a bike with this engine run in?
« Reply #11 on: September 15, 2010, 05:28:21 PM »
The unfortunate answer that it must run in the same class as GSXR 1000, Kawi 1000 and CBR 1000 ... the engine is not going to be competitive against much more efficient modern designs ... I would build a chassis and run it without any record expectation ... be the fastest Westlake .... Joe

Offline Stan Back

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Re: What class would a bike with this engine run in?
« Reply #12 on: September 15, 2010, 05:43:59 PM »
And (no offense, Bill) probably the coolest.
Member of the San Berdoo Roadsters -- "California's Most-Exclusive Roadster Club".
Celebrating 67th anniversary of racing on the salt.

Offline Dakzila

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Re: What class would a bike with this engine run in?
« Reply #13 on: September 15, 2010, 05:48:28 PM »
Unfaired, special chassis, 1000cc, no added boost? You'd end up running in Special Construction, in the A/G 1000cc class.

Unfortunately for those of us who run in this class they (the powers to be) allow modern sportbikes to remove their faring and run in the same class without any chassis mods, so as Joe said earlier in this string it's hard to be competitive running an older style engine in this class.

Still it would make a great looking ride and I'd like to see it run....good luck.

Ron  B
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"It's not about what you did.....It's about what you do!"

 "Regret is part of the aging process and should never be confused with failure."

Offline Nortonist 592

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Re: What class would a bike with this engine run in?
« Reply #14 on: September 15, 2010, 05:54:54 PM »
And (no offense, Bill) probably the coolest.

No Doubt.  And in a wideline ABSOLUTELY no doubt.  But he hasn't run yet.  You know the old saying.  If you want rabbit stew first you gotta catch a rabbit.
Get off the stove Grandad.  You're too old to be riding the range.