Moto GP rep rebuild and restore,

[Danman109]

The L9 (the old bike)



The L2 (the new bike)




The Plan (which is never adhered to and changes according to the mood im in at the time!)

The L9 rocker cover gasket needs changing, the L2 head gasket needs changing first of all!

I want to tune the L9 engine, some of the aspects have gone out of the window such as blueprinting and forged pistons because the parts are no longer available

But smoothing the ports, re-grinding the valves, skimming the head and lightening + chamfering the crank and getting kent cams etc are certainly on! I would love to get some flatsided carbs if anyone has them???

other than the engine I have a weight target of 135kg and a power target of 75bhp.. given the L9 engine had a dyno proved 62.4bhp with only an airbox mod and stainless downpipes i hope this is achievable!

[Danman109]

I could be wrong.. but im sure its not supposed to be this shape!



There's supposed to be an engine mount here too?



Out comes the engine



wiring loom and subframe extracted,



Big mess in the garage now! progress at last though! rocker cover gasket next!

[MrLuke]

Looks like the makings of a good project, will keep my eye on it How much was the rocker gasket btw? And where from? Cradleys on eBay want £39 for the little bit of rubber!

[AFM327]

Toecutter has forged .5, 2.0 and 2.0 forged omega pistons, there's a sticky at the top of the racers corner.

[Danman109]

Looks like the makings of a good project, will keep my eye on it How much was the rocker gasket btw? And where from? Cradleys on eBay want £39 for the little bit of rubber!

Thanks yeah that's about the price i paid for it, I prefer to pay for genuine though (where i can) ring them up and see what they say, sometimes you can get something off the price if your not paying via paypal.

[Danman109]

One set of spare trackday panels all prepped and ready for the first coat of primer! (One of my mates did these for me he's much better at it than i am!!)



Rust removal, lets see if it works, its fizzing!!

[Danman109]

The vinegar worked!! i never doubted it however after wire brushing and rinsing the bolts off with water they went rusty again in 20 mins!
:-/
had to wire brush each one individually (again) and spray with WD40 immediatly.. not sure how this will work in the long run?
In the meantime £125 titanium engine bolt kit from probolt? hmmm...

[AFM327]

The vinegar worked!! i never doubted it however after wire brushing and rinsing the bolts off with water they went rusty again in 20 mins!
:-/
had to wire brush each one individually (again) and spray with WD40 immediatly.. not sure how this will work in the long run?
In the meantime £125 titanium engine bolt kit from probolt? hmmm...

The 7075 aluminum bolts are lighter and plenty strong for that use and they're a bit cheaper too.

[Danman109]

The 7075 aluminum bolts are lighter and plenty strong for that use and they're a bit cheaper too.

which is most tried and tested in the race 400's? i know 7075 bolts are about 85% strength of the Ti bolts.. not sure if the peace of mind would be worth it.. we'll see, still bouncing ideas around still at this point! I'm sure others have asked this already!

[AFM327]

The 7075 aluminum bolts are lighter and plenty strong for that use and they're a bit cheaper too.

which is most tried and tested in the race 400's? i know 7075 bolts are about 85% strength of the Ti bolts.. not sure if the peace of mind would be worth it.. we'll see, still bouncing ideas around still at this point! I'm sure others have asked this already!

I would say it depends on where your using them, except for head bolts how many bolts on the motor have high torque values? 85% of ti is a pretty good percentage for lighter and cheaper.

[Danman109]

After vinegar


and subframe broken down ready for powdercoating

[Danman109]

It Lives!!

The L2 is running on L9 carbs

Still confirms that it's the headgasket thats gone because after a few trips up and down the road the coolant was dribbling out again

Oh well.. another engine to drop out then..

[Danman109]

So the situation is worse than previously thought.. the impact has cracked the head around the exhaust ports.. new head needed...

need to check the oil filter seat for cracks and deformation too.. if it too is cracked then its game over for this L9 engine

[Danman109]

So the Moto GP rep engine was dropped this weekend to do the Head Gasket which has thrown up a few unexpected issued

There are a couple of worn rocker arms like this one:

]

I'll take all of the exhaust arms off the fractured L9 head and use them to replace the inlet arms on the L2 as i have a brand new complete head on the way!

The cam chain is almost maxxed out and the previous owner had cleverly disguised a rocker cover leak by cleaning the visible parts of the engine before i bought it :smt013

Other than that while the engine was apart i took the opportunity to clean the cheese off the pistons:




Looking much better now! Working in the garage at -2degrees isnt much fun though!

[mongo]

Take the cylinder head off the l9 engine and get it pressure tested.

Looks like from the picture, that it may just be the exhaust headers that have bent and cracked the metala/alloy around the headers, which stick out from the head. A bit of alloy weld then smoothing it back off if oyu sitll wnated to use the l9 engine...