repairing holes in intake on over-ground cylinder.

[m in sc]

I know this is the old school way of putting in big reeds, but IMHO, epoxy doesn't belong in an intake tract on anything.  That's being said, when franks lost a cylinder due to a silencer/exhaust issue, upon inspection at the gap, we realized the epoxy was coming loose on his fresh cylinders. all 4 sides had holes. I offered to weld them up. Mind you, im not the best aluminum welder but i can def seal a hole. we had to preheat the 1st cyl to 550 degrees to get it to actually weld right. the second one, we took to my friends shop on Saturday and threw down with a legit industrial tig welder with 2x the amperage. I was filling it with 1/8" rod in the video. lol. 

either way, now safe to run.  No leaks, i checked. also checked and squared surface of reed box incase it warped, and retapped holes. rehoned cyls, greased bores to keep them rust free for shipping.

just use smaller v force reeds if you must. there's no need for this unless it s flat out race bike, and then just weld it up 1st.

Back to VA it goes today.













yours truly trying not to liquify the whole thing. 1st time on this particular welder. Oh, also the pedal had a propensity to stick, so i zapped poor David later because it didn't shut all the way off. 

[Hawaii-Mike]

Zapped poor David - ouch!

Nice work with the welding.

[Kawtriplefreak]

Excellent work!!! David probably liked it

[m in sc]

hes getting PT on that arms shoulder from old inuries. of course, thats the arm that took the jolt.     

[85RZwade]

I assume you charged him for the electro-shock therapy? A donut is your usual fee, right?

[Czakky]

  what was the intake he was using?

[m in sc]

its the cylinder was the issue. intake boot doesnt matter really.

[1976RD400C]

When I was having my cylinders ported and bored the machinist called and said the squared surface for the reed box was warped and not flat anymore. He refaced it.

[85RZwade]

It's been a long time since I did any TIG welding; as I recall, the rocks were still hot. Are the C-clamp and vise-grips on the cylinder as heat sinks?

[m in sc]

Are the C-clamp and vise-grips on the cylinder as heat sinks?

actually, thats a backing plate for behind the holes. thats to keep the rod from just flowing though. its Elkonite, 10/30. so, aluminum wont stick to it. (basically tungsten, molybdenum and copper. ) kinda like taping a hole when patching a fuel tank so the sealant wont run out.

the last thing i needed was a heat sink for the most part. it shed heat pretty well. except right under the weld itself to keep it from melting thru. I actually cut it in a wedge shape so it would fit flush against the side of the intake. that's why one side is dressed more than the other, it shifted a bit on the 1st run.

[Frank B]

I completely missed this.. I'm not here nearly enough.    

Thanks again Mark!

This whole debacle started because I didn't pay attention and I bought banshee Vforce reeds instead of YZ85 reeds for my stage 2 top end build. Garrett @ GRA2strokes did the excellent top end work, and just did what his dumb customer wanted and made the intakes big enough. I also rushed the assembly once the parts were in my hands because I was trying to get it done before going to the Gap and most likely got the epoxy mix wrong. Lesson learned!  Remember the tips shared on the board and order the right parts next time!!