Thunderbike Questions

[LWT Racer]

Oil going through cylinders?

[LWT Racer]

Doesn't it say that the engine has to be from the same production model motorcycle?

I had some questions about the thunderbike rules too.  It says Thunderbike Lightweight allows for '90-'92 up to 650cc.  So what do they judge the year by?  The number stamped on the frame or the number stamped on the engine cases or do they have to match?  The reason I ask is I have a 1994 FZR600.  From '90 to '98 they are almost completely unchanged (except for foxeye FZRs)  I assume I couldn't race this in the Thunderbike LW class?  But according to the "engine from the same production model motorcycle" I could buy a '90-'92 FZR600 frame and swap all of my '94 stuff into it.  Seems a bit stupid since the '90-'92 FZR600's are identical to my '94 and all of that work would be just to have a frame that said '90-'92...

You cannot swap engines in Thunderbike.  If the model changed according to Yamaha, then you can only use the 90-92 motor.  That being said, SV and ER6 guys use cross generation motors as they are basically the same. So idk...

[d0wn5h1ft]

You cannot swap engines in Thunderbike.  If the model changed according to Yamaha, then you can only use the 90-92 motor.  That being said, SV and ER6 guys use cross generation motors as they are basically the same. So idk...

That's the thing, the FZR600 model was made from '89-'98.  With the only major change being a wider wheel and 4 piston calipers in '90 which doesn't matter because brake upgrades are apparently unlimited in Thunderbike.  Why is it then you can only use '90-'92 FZR600's in that class?  I wouldn't have a problem buying a '90-'92 frame and swapping all my '94 components into it I guess but that seems like a lot of work seeing as they're the same Yamaha model name

[britx303]

Doesn't it say that the engine has to be from the same production model motorcycle?

I had some questions about the thunderbike rules too.  It says Thunderbike Lightweight allows for '90-'92 up to 650cc.  So what do they judge the year by?  The number stamped on the frame or the number stamped on the engine cases or do they have to match?  The reason I ask is I have a 1994 FZR600.  From '90 to '98 they are almost completely unchanged (except for foxeye FZRs)  I assume I couldn't race this in the Thunderbike LW class?  But according to the "engine from the same production model motorcycle" I could buy a '90-'92 FZR600 frame and swap all of my '94 stuff into it.  Seems a bit stupid since the '90-'92 FZR600's are identical to my '94 and all of that work would be just to have a frame that said '90-'92...

Sorry,i always get confused.....is the foxeye what later became the yzf600? I know the headlights you are talking about,but i never checked to see if it was a re-bodied FZR,or the frame was different too. I wish CCS would just have a 90's superbike/forgotten era class for Pre-99ish bikes ::) Especially right now with the Mid_atlantic V6+V7 guys looking for a place to race without having to drive all over the country.Thats how i got here in the first place.

[Woofentino Pugrossi]

Doesn't it say that the engine has to be from the same production model motorcycle?

I had some questions about the thunderbike rules too.  It says Thunderbike Lightweight allows for '90-'92 up to 650cc.  So what do they judge the year by?  The number stamped on the frame or the number stamped on the engine cases or do they have to match?  The reason I ask is I have a 1994 FZR600.  From '90 to '98 they are almost completely unchanged (except for foxeye FZRs)  I assume I couldn't race this in the Thunderbike LW class?  But according to the "engine from the same production model motorcycle" I could buy a '90-'92 FZR600 frame and swap all of my '94 stuff into it.  Seems a bit stupid since the '90-'92 FZR600's are identical to my '94 and all of that work would be just to have a frame that said '90-'92...

When I raced a 93 f2 Kevin allowed it in thunderbike since it was unchanged from the 92 model. Also he said fzr600 up to 98-99 also allowed due to unchanged from 92 and earlier.

[d0wn5h1ft]

When I raced a 93 f2 Kevin allowed it in thunderbike since it was unchanged from the 92 model. Also he said fzr600 up to 98-99 also allowed due to unchanged from 92 and earlier.

I assume you just had to email him prior to get approval?  Was there any sort of extra race registration things you had to do to run it?

[Woofentino Pugrossi]

I assume you just had to email him prior to get approval?  Was there any sort of extra race registration things you had to do to run it?

Yeah I emailed him. Kept a copy in my toolbox in case tech said no.

Brit the yzf600 was a totally different bike from the fzr600.