is this a possibilty?

[coley13]

this is more an engine question but the only reason i'm thinking this is for possible gen3 conversions with "Y" clearance issues.

i notice Bobs build is focusing on as little Fab work as possible for that Factory look.

i dont know the figures or how close the exhaust is to the Y on gen 3 but had anyone thought of having the "deck" or "cases shaved" which ever way you wish to word it. Have a "shorter con rod" to suit to keep port timing the same in an attempt reduce the exhaust and "Y" clearance. (as to eliminate any cutting or welding)

as i said i dont have figures but as an example

say i need 6mm clearance at the Y is it possible to lower the cylinder by as above method by shaving 6mm keeping the port timing the same by having a 6mm shorter rod but lowering the capacity of the engine to roughly 450cc. if it's possible you will loose some of your engine capacity but might end up with and engine that revs a little harder


this might not be a viable option but i'm just trying to think outside the square in attempt for you guys to get these engines fitting with very little fab work.

any thoughts would be great on the matter. it's only a very rough theory at this stage. i'm sure theres stuff i probably havnt thought through properly but lets put our heads together and see what we can come up with.

[AlisoBob]

Welding up the jug and repositioning the exhaust outlet lower while retaining the stock port timing is also a possibility...

Great train of thought Coley!

[coley13]

i see lots off builds where the engine gets a full overhual aswell so i thought why not look at engine mods instead to make them fit better.

never know. if someone was to do the math and work it out they might end up with a humbdinger of an engine whist retaining a realativley stock chassis.


i'm poor and got no money so i'd say it would be a long long time before i get to attempt a conversion.

Bob your the one who's inspired me into thinking of different possibilities with your build, it seems everyone else seems to start cutting chassis and then start scratching there heads on whats the best way to weld it back together

[AlisoBob]

Bob your the one who's inspired me into thinking of different possibilities

Then I've done my job in life...

[lewisclan]

Bob your the one who's inspired me into thinking of different possibilities

Then I've done my job in life...

Yes kill Bob now

[britincali]

Bob your the one who's inspired me into thinking of different possibilities

Then I've done my job in life...

Yes kill Bob now

[ou812]

A 85 or 86 motor is going to drop you 4mm and on a stock exhaust port the sleel flange could have it's holes ovalled and dropped somewhat without it's inner top edge exposed in the port. The new style pipe also makes that motor much more friendly to ride.

[dannygraves]

my gen-1 is an '86 and the head stay mount is almost exactly 5mm lower, so I would imagine the exhaust port would be as well.
but the big problem is that the short rods aren't being made anymore, so everyone is putting in a 5mm spacer and a new rod...
good idea though.