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New 2008 CR500AF, Want to put an 87 Top end on

Posted: October 14th, 2008, 4:03 pm
by belandbroc
I should see a new 500af with the ' 08 chassis show up at my door in the next 5-10 days. I requested an '87 motor, but they do not go off of their current 'new motor' option. I want to go with the '87 top end.

What do I need to buy and apply to have the '87 hit that has never been repeated in my opinion?

Thanks in advance.

Posted: October 14th, 2008, 4:09 pm
by britincali
The "hit" is nothing more than port timing, get it ported.

Posted: October 14th, 2008, 7:17 pm
by 100hp honda
there was nothing special about '87 cylinders. not that theres anything wrong with them either but you get what im saying

Posted: October 14th, 2008, 8:56 pm
by nmdesertrider
get an 85 if you want hit

Posted: October 14th, 2008, 8:58 pm
by britincali
nmdesertrider wrote:get a top end portjob if you want hit
Fixed :D

Posted: October 14th, 2008, 9:40 pm
by 100hp honda
i wouldnt put a old model cylinder on a new model case anyways. the sleeve outside diameter is too small and wont fit snug into the crankcase like its supposed to.... (many dont know this but the sleeve is supposed to fit snug into the crankcase and adds support in that area, the dowel pins also add support. if the sleeve isnt snug then it defeats the purpose of why its there). not to mention the new model cylinders are alot stronger in the bottom stud area. the new model jugs is where its at brotha :wink:

Posted: October 15th, 2008, 6:44 am
by Roostius_Maximus
ok, its going to be outrageously oversized, but heres a pic of a factory '88 (same as '87) jug on '88 cases, its got that much room arround it, and at the floor, i dont agree with the "snug" comment, thats why the dowell pins at the side of the jug locate it on the case, however the size is close there as to tighten the scavenge area of the crankcase. The '87 does have better ports yes, but an '86 is even better and the port timing is trick, to achinve the same port timing in this '88 as my '86 i need to deck the cases .030, use a cometic thin base gasket and use an '89+ cyl head to get a chamber large enough for the piston to rise out of the cyl .018

Image

Posted: October 15th, 2008, 3:40 pm
by 100hp honda
Roostius_Maximus wrote:ok, its going to be outrageously oversized, but heres a pic of a factory '88 (same as '87) jug on '88 cases, its got that much room arround it, and at the floor, i dont agree with the "snug" comment, thats why the dowell pins at the side of the jug locate it on the case, however the size is close there as to tighten the scavenge area of the crankcase. The '87 does have better ports yes, but an '86 is even better and the port timing is trick, to achinve the same port timing in this '88 as my '86 i need to deck the cases .030, use a cometic thin base gasket and use an '89+ cyl head to get a chamber large enough for the piston to rise out of the cyl .018

Image
we will agree to disagree on the whole subject. if belandbroc wants a '87 jug, then by all meens thats the one he should buy :D

Posted: October 15th, 2008, 3:55 pm
by Roostius_Maximus
i agree, dont let it become one of those things thats going to distract you from having fun.
if you're going to be haunted by the "what if" factor, then solve it by dooing what you need to.

Posted: October 15th, 2008, 4:27 pm
by TYSTYX
Geezus......can you make the pics any larger ????