Joined Jun 2007
4K Posts | 1K+
south east WA Australia
heres a bushmechanic tool I made years ago when I had absolutely no spare money 
Bushmechanic Mongrel 628 Trailbike
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- 628 bushmechanic mongrel trailbike
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
machined valve spring seats deeper to get 65lbs seated force from the KTM dual valve springs, and faced off the upper surface of the head parallel to the cam bearing tunnel, also faced off the rocker cover parallel to the rocker arm pivots
0.75mm thick tapered spacer shell held in with brass rivets and bog, bolted together and re bored the tunnel 0.75mm higher up
made some room for serious head studs
with the top surface of the head properly parallel to the cam and the rocker arm pivots I had to face off the lower head surface parallel to the upper surface to make the cam come out parallel to the intermediate shaft
0.75mm thick tapered spacer shell held in with brass rivets and bog, bolted together and re bored the tunnel 0.75mm higher up
made some room for serious head studs
with the top surface of the head properly parallel to the cam and the rocker arm pivots I had to face off the lower head surface parallel to the upper surface to make the cam come out parallel to the intermediate shaft
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Joined May 2014
115 Posts | 23+
Tassie
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
cut valve pockets with a valve
cam nicely timed itself slightly advanced with the cam lifted
needed a bit more piston to valve clearance, could have done another job in the mill but thought id show how it works with a fly cutter made from a valve.
cutter made from welding a blob onto an old valve and grinding some edges on it
i used a few spacers at the top to limit the cut depth to 0.2mm at a time
few more pics etc of other tools
cam nicely timed itself slightly advanced with the cam lifted
needed a bit more piston to valve clearance, could have done another job in the mill but thought id show how it works with a fly cutter made from a valve.
cutter made from welding a blob onto an old valve and grinding some edges on it
i used a few spacers at the top to limit the cut depth to 0.2mm at a time
few more pics etc of other tools
bushmechanic said:
bushmechanic said:some more pics
the sandpaper glued to the valve is a nice one
commercially available for use with a drill and mounted in the valve guide
or use a lathe
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
recut valve seat Neway cutters
one of the seats had a spot of corrosion that didn't clean up with a light lap so needed a re cut
nice metal underneath, the rust was quite deep, had to take 0.2mm off
narrowed, cleaned up with 30 and 60 deg cutters and lapped
one of the seats had a spot of corrosion that didn't clean up with a light lap so needed a re cut
nice metal underneath, the rust was quite deep, had to take 0.2mm off
narrowed, cleaned up with 30 and 60 deg cutters and lapped
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Joined May 2014
115 Posts | 23+
Tassie
I see u taken some meat off top piston ?! Isn't that gonna change compression ratio "less" just
Wondering how ya know not take to much off? Understand more clearance for the valves
Just wondering
Wondering how ya know not take to much off? Understand more clearance for the valves
Just wondering
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
yes about 0.2cc total, 0.1cc per pocket ... but i took some off the head as well so it will be about the same or higher CR.
its only a trailbike so im not too fussed about the CR, as long as its between 11.5 and 12.5 im happy
its only a trailbike so im not too fussed about the CR, as long as its between 11.5 and 12.5 im happy
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
..
http://husaberg.org/marketplace/11326-billet-cylinder-head-24.html
I made a tensioner full radius instead of the flattened off Husaberg design
to get the chain back to the original position so I can use a .8mm head gasket.
Still needs a little development, as the chain wears the tensioner will press the chain into the cam sprocket, but I am close
This is how I do my CAD analysis
Next Is a manually adjusted chain tensioner.
Cheers spanner
http://husaberg.org/marketplace/11326-billet-cylinder-head-24.html
I made the groove in the head
Uploaded with ImageShack.us
on the pics you can see what's going on when a stud broke :? , it happens on 6 gear at 210 km/h
regarding the cam chain , I put two chain tensioner rail and two cam adjuster one in the stock place and the other one in the front , so I can adjust my timing easily :wink:
Joined Sep 2007
782 Posts | 291+
???
Yes looked at putting a curved guide on the front side, but came to the conclusion that it was much easier just to make a full radius rear slipper.
Wondering if some noise is generated from that front guide flapping around.
Are you shimming the cam to get the chain tight Bushie?
That water transfer hole and the m6 cover mounting hole could have been better placed at allow for more chain adjustment.
The tensioner is a fair way out to start with, even with a new chain and stock deck/gasket.
Love that post valve porting
Wondering if some noise is generated from that front guide flapping around.
Are you shimming the cam to get the chain tight Bushie?
That water transfer hole and the m6 cover mounting hole could have been better placed at allow for more chain adjustment.
The tensioner is a fair way out to start with, even with a new chain and stock deck/gasket.
Love that post valve porting
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
post valve porting LOL like a postnatal class
yes it is kind of a shim under the cam 0.75mm thick at the bottom, and thinner higher up. I would have welded it up and then rebored but my brother has the tig for a while, I also discoverd 0.75 was not quite enough so will re do it to 1mm another time.
yes I think your rear curved guide is a better solution than putting one on the tension side of the chain, yes could be noisy .... must be a pretty wild dance going on with the chain would be great to do a slo mo vid through a plastic cover
sealed the cases together this afternoon, jeebus that took me a while, 50 different mongrel parts so nothing fitted straight up
yes it is kind of a shim under the cam 0.75mm thick at the bottom, and thinner higher up. I would have welded it up and then rebored but my brother has the tig for a while, I also discoverd 0.75 was not quite enough so will re do it to 1mm another time.
yes I think your rear curved guide is a better solution than putting one on the tension side of the chain, yes could be noisy .... must be a pretty wild dance going on with the chain would be great to do a slo mo vid through a plastic cover
sealed the cases together this afternoon, jeebus that took me a while, 50 different mongrel parts so nothing fitted straight up
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Joined Jun 2007
4K Posts | 1K+
south east WA Australia
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
drive pinion lockwasher
Ive never had a drive pinion come loose with proper use of loctite but this gear has a history of coming loose and is very loose on the crank, I can push it on by hand.
so JBS idea, lock washer
ground a flat section on the gear and machined 1mm off the nut. the nut has a huge lead in champher where there is no thread so this does not affect the strength of the nut.
Ive never had a drive pinion come loose with proper use of loctite but this gear has a history of coming loose and is very loose on the crank, I can push it on by hand.
so JBS idea, lock washer
ground a flat section on the gear and machined 1mm off the nut. the nut has a huge lead in champher where there is no thread so this does not affect the strength of the nut.
Joined Sep 2013
369 Posts | 209+
canolbarth cymru
I ended up lockwiring mine, I'd have liked to have used your tab washer idea but when we cut a new thread on the crank we couldn't get as many threads as we would of liked. We thought a 1mm tab washer would have used up a little of our thread area. Thoroughly cleaned, Loctite 2701 and with the help of my engineer mate we clicked it up to 105nm, 5nm at a time!
Sorry to hijack your thread! Great work by the way!!!:spin::spin::spin:
Sorry to hijack your thread!
Great work by the way!!!:spin::spin::spin:Attachments
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
found if i put grooves in the clutch plates they last much longer
they are about 0.2mm deep and staggered from one side to the other so they don't align and create a weakpoint.
oil pickup slots in the clutch pressure plate
pic of the LHS before the cover goes on. to make the gasket reusable i put loctite 518 on the case then the gasket on top of that, then put anti seize compound on the cover. cover bolts tourqued to 8Nm, have only ever bought 2 clutch cover gaskets.
the groove for the o ring on the water passage measured 1.6mm deep on this engine, my other 2 engines it measures 0.8mm deep so i put a shim in the groove.
shimmed the kickstart shaft to 0.2mm axial play, needed a 0.6mm shim to get there.
also had to take 0.8mm off the silver spring collar on the gearshift shaft to get the 06 cover to fit on the 02 cases.
Spanner sent me some internal engine bling, oem water pump shaft oil seal and bearing left, same size bearing machined thinner on right
for use with a std shaft seal
LHS is bolted up, ignition cover needs some wizard hat tricks, engine nearly done.
they are about 0.2mm deep and staggered from one side to the other so they don't align and create a weakpoint.
oil pickup slots in the clutch pressure plate
pic of the LHS before the cover goes on. to make the gasket reusable i put loctite 518 on the case then the gasket on top of that, then put anti seize compound on the cover. cover bolts tourqued to 8Nm, have only ever bought 2 clutch cover gaskets.
the groove for the o ring on the water passage measured 1.6mm deep on this engine, my other 2 engines it measures 0.8mm deep so i put a shim in the groove.
shimmed the kickstart shaft to 0.2mm axial play, needed a 0.6mm shim to get there.
also had to take 0.8mm off the silver spring collar on the gearshift shaft to get the 06 cover to fit on the 02 cases.
Spanner sent me some internal engine bling, oem water pump shaft oil seal and bearing left, same size bearing machined thinner on right
for use with a std shaft seal
LHS is bolted up, ignition cover needs some wizard hat tricks, engine nearly done.
Joined Jun 2007
4K Posts | 1K+
south east WA Australia
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