Page 1 of 1

Gear box rebuild - problem

Posted: Sun Jun 07, 2009 12:45 pm
by Davw
Am rebuilding an engine and changing crankcases - damage to the original cases meant this was a must. However - gearbox internals are fine. - Only one small problem which I onyl spotted today :smt009 when rebuilding the box and am hoping someone has dealt with this before.

At some stage Kawa must have changed the design of the fixing point and spring for the gearchange drum set lever arm.

In my replacement crancases the fixing point is on the bottom left of the drum housing (as you face it) - the same as in the manual (page 8-14) however in my engine the lever arm is fixed on the bottom right and has a "captive spring" which acts on the lever arm and bears on the wall of the crancase- the design in the manual (which is consistent with my replacement crankcases) looks as though the spring is tensioned between the arm and a fixing point on the crankcase.

I know this is a bit difficult to explain without photos and will take some later but just wondered if any engine builders/ rebuilders had faced this problem

Re: Gear box rebuild - problem

Posted: Sun Jun 07, 2009 2:04 pm
by Davw
It looks as though I have got a pre-93 replacement crankcase (an L1 or L2) and the original engine is an L3 or later - the microfiche shows the different design of the lever/ spring -

Looks like I need to drill and tap the crankcase to create a fixing point for the lever arm - however. Before i set of down this road are there any other incompatabilities to be aware of between this crancase and the later engine

Re: Gear box rebuild - problem

Posted: Sun Jun 07, 2009 6:10 pm
by RedexRobB
never seen here that there were any changes in early model engine, although rumoured, so this is a first for us. I think only Zimm would know any more on the matter, hes done alot of engine work on these.

Re: Gear box rebuild - problem

Posted: Sun Jun 07, 2009 7:52 pm
by Davw
Thanks Rob - it was a classic "oh toad" moment as seconds before finding this problem I thought "this is all going really well" - not.

I have asked Drew if he has come across this before and thought maybe Cargo/ Zimm might have seen it but to be honest I think I either need to drill and tap the crankcase or get a later model crankcase

I can confirm though - not all L crankcases are compatible with all engine internals!!!! :smt009

Re: Gear box rebuild - problem

Posted: Sun Jun 07, 2009 11:10 pm
by WelshD1K
hey mate might have a crank case hew ill get some pictures if you need one

Re: Gear box rebuild - problem

Posted: Tue Jun 09, 2009 11:02 am
by Davw
WelshD1K wrote:hey mate might have a crank case hew ill get some pictures if you need one
Sounds good - need a pic of the area behind where the clutch sits

Re: Gear box rebuild - problem

Posted: Tue Jun 09, 2009 11:26 am
by masterofinsanity
interesting as kwak did revise some engine components through the L models but what? is another question.

Re: Gear box rebuild - problem

Posted: Tue Jun 09, 2009 4:56 pm
by Davw
Baz - spoke with Brian at AMS and he reckons that this is the only incompatability between the early crankcases (L1/L2) and the later. The much later changes (L9) are not incompatabilities (upgraded con rods, barrels etc)

I will take some photos of both so that it is on the site

Re: Gear box rebuild - problem

Posted: Wed Jun 10, 2009 9:35 am
by masterofinsanity
cheers mate!