illegal big bores-FYI

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#1
I have been checking on the legality of running bored engines like Eric Gorr , Max-Power and RPM build. I questioned the AMA on using a 310 kawasaki built by Eric Gorr in the open class in the AMA Hare Scrambles Series. I was told that these engines are illegal for cross country competition because they were bored and replated instead of sleeved with a liner.

This is the answer I got from the AMA......

I know this is going to sound stupid but these are the rules. You can overbore a cylinder .080 inches and still be legal to run in the same class. I am assuming that you have a 1992 or older model. That being the case then .080 over fro you would be 265.5cc. To move to the next displacement class the following applies.
From Chapter 3 , Section C. in the rule book:
The use of kits or sleeving is allowed in all forms of off-road competition in
the 200cc and above classes only. Kits must change the displacement a minimum
of 10% beyond the AMA recognized class limits and must have the correct
displacement stamped on the side of the cylinder
From Chapter 1 - Definitions:
KiT - An over the counter, available for sale to the general public,
assembly of parts designed to increase the
displacement of a motor a minimum of 10% beyond the AMA recognized class
displacement for the purpose of changing classes. A motor so modified must
have the correct displacement stamped on the side of the cylinder.

SLEEVE A cylinder insert.

By overboring only, what you have done is not legal in AMA competition. To
change your machine to the open class you will have to have a big bore kit
installed.

This has happened because the rule allowing kits and sleeving was added a few
years ago and the previous rule was still in place that prohibited riders from
modifying their machines to change classes. If you think this rule needs to be
changed then you must contact your AMA congress delegate. He can be located on
the AMA web site at AMADirectlink.com in the "AMA Sports" section

I checked the GNCC supplemental rules which have been approved by this office
and they read:

4. Open Classes (Motorcycle) - If a manufacturer
produces an open size machine(HON & KAW), no 250's
will be allowed to use Big Bore Kits. If a
manufacturer does not produce an open size
machine(YAM & SUZ), 250's will be allowed to use a
manufactured Big Bore kit. You cannot over-bore a 250
engine to run in the open class. Cylinders must be
stamped with new engine displacement

As you can see a 308 overbore is not allowed in
the GNCC series or other cross country type events.
If you have any other questions please contact us
again.

Sincerely,

Roger Ansel
AMA Sports Manager
 

HiG4s

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#2
There are a lot of things in the AMA rule book that local clubs over look and even the AMA overlooks.

like in enduro racing

3. Equipment
A rider may not start if any state-required equipment is not in working
order at the beginning of the meet.

Every place I have ever been they require a licence plate to ride enduros, once that plate is on the bike, by this rule must meet state requirements to be fully street legal but I seldom see this enforced.

Also in motocross

(4) Foot rests and levers
(a) All foot rests must be covered with at least one-quarter inch
rubber or plastic (not tape), and must fold backward at a 45-degree
angle for at least 50 degrees of movement. Folding
footpegs are not required on GP road racers.
(b) The length of the foot rest pivot point to the frame, engine or
transmission must not exceed two inches and may not be lower
than the crankcase or frame, whichever is lower.
(c) The gearshift and brake pedal also must be covered by rubber
or plastic.
(d) Protective coverings on levers and pedals are not required for
motocross, enduros, hare and hound, hare scrambles, trials,
observed trials, hillclimbs, or ice race.

It says that protective coverings are not required on levers and pedals, but by this rule, rubber is still required by AMA rules on footrests!!!! How long has it been since dirt bikes had rubber footpegs.

Technically what Eric does is the same as sleeving, perhaps if he stamped the new CCs on the cylinder.
 
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#3
Eric does stamp the new cc size on the cylinder. He did on mine when he bored it.

The rules are not up to date with the technology available. Sleeves are out dated , but if you are protested the AMA is going to go by those out dated rules.
 

HiG4s

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#4
So I should get some rubber footpegs, enter a national and protest everyone that beats me, which would be everyone.:p
 
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#5
I believe it says somewhere that motocross (and some other) bikes are exempt from the 'rubber footpeg' rule. I'll have to look...
 

wardy

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#6
OK lets go over this a little since

I was the one that ask for and sponored the over bore kit rule to allow class jumping. if you have eric or anyone bore and do the ten percent increase in size I would say and consider that a "kit" to increase for the next class. The main reason the 10% and the Kit rule was in there was to stop riders from using an .80 overbore to go to the next class, then only to return to the 250 class when they felt like it.............hence the overbore rule which came out of ama congress 5 years ago and I was on that committee. Harescrambles, Enduros etc could possibly not accept that rule change but it is under Motocross and the difinition of a "sleeve" is exactly my wording i proposed.
so basically instead of saying "i overbored my cylinder to run open class" say "i bought a kit to increase my displacment" (its basically the same dam thing) included in the kit was a bore job, piston, rings etc. If thats not what is acceptable then for 2003 the rule can be addressed, 2002 is already in the works and would be hard to implement at this time. AJ Waggoner was invovled in this rule deal also.

rubber foot peg stuff doesn't apply to motcross it is mainly a dirt track thing. Its real easy to miss quote the ama rule book if it isn't read completely. I have messed with that book since 1989 on a weekly basis and still find things i didn't see before.


by the way this thread would have gotten a lot better response in the AMA , District forum thats where these questions get answered quickly......

thanks
 
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#7
got an updated response from the AMA , now they tell me it is legally a kit since anyone could buy it

which means .... the 310 is legal in AMA National Hare Scrambles but not legal in GNCC Cross Country races

which makes the question..... There are several GNCC races that are combined points races with the AMA Hare Scrambles series , which set of rules do you go by?
 

wardy

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#8
thats easy

if gncc is an ama sanctioned event, then the rules from ama should apply or even supercede GNCC rules. But then don't count on that with that situation.