Head/Cylinder issues

Y

yamaslut

Guest
OK... I keep blowing orings like it's going out of style... (getting pretty tired of wrenching on the beach) The up side... I can pull my head and change orings in like 10 min now... yipeeee...

I'm running an ADA head. (the older one) w/ acorn nuts
Anyway.... I had a cyl drop when I first got my motor. Had it decked and so on.. It's fine now... My theory is that when the cyl. dropped it caused the dome to seat crooked and caused uneven wear on the inside top of the head where the dome meets the head itself... Has anyone seen uneven wear on a head like that before???? I can't understand what else it could be.. anyway, I changed the domes out and the old ones I had in there had uneven wear on the tops... The new one were perfect and lasted a few rides... When I pulled the head to inspect the new domes were unevenly worn and it looks like it was caused by the head... Do I have to get a ned head, or can this be fixed??? I will snap some pics tonight to show the wearing on the inside top of the head and the top of the dome itself. Another thing... the top of cyls are not clean anymore... there is an indent where the dome (looks like) it rubbed down the deck of the cyls... Thanks for any advice...

I really hate this head and have lost all hope in riding longer than 1 hr w/o blowing an oring...:frown: :frown: :frown: :frown: :frown:

btw - anyone w/ a head that will fit a 84mm bore, let me know... girdle or not
 
SkiDaddy

SkiDaddy

Just Havin' Fun!
Location
Orange City, FL
After having similar troubles w/an R&D head (including dome cracking) I bought a new ADA & haven't had those problems anymore......

Not cheap, but if you can sell your current head to someone w/access to a milling machine you can recoup most of the expense.:sneaky:
 
Y

yamaslut

Guest
SkiDaddy said:
After having similar troubles w/an R&D head (including dome cracking) I bought a new ADA & haven't had those problems anymore......

Not cheap, but if you can sell your current head to someone w/access to a milling machine you can recoup most of the expense.:sneaky:
Click to expand...

thanks bob.... I just don't have 400$ for a new one...
 
S

sflsurfrider

it sounds like the dropped sleeve caused the dome to vibrate around which ate away at the head shell. if thats the case, it will we an ongoing problem until you replace the head shell.

just 1 theory.

id take out the orings and do a dry fit with the dome in the shell and see if one dome is able to recess into the shell more than the other. use a straight edge to check.
 
Y

yamaslut

Guest
Matt_E said:
Milling the head will necessitate milling the domes, won't it?
Click to expand...

the issue is where the head itself mates to the dome on the upper side of the head (where the middle sized oring is at)
 
Matt_E

Matt_E

steals hub caps from cars
Site Supporter
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at peace
Damn....I had a Riva kit for sale just a couple days ago.
I got an MRD head, with non-removable domes, that's for sale.
But it would require machining to get the domes opened up and enlarged.
It's 34cc and for 81-83mm bores.
Probably not something you want.
 
Y

yamaslut

Guest
sflsurfrider said:
it sounds like the dropped sleeve caused the dome to vibrate around which ate away at the head shell. if thats the case, it will we an ongoing problem until you replace the head shell.

just 1 theory.

id take out the orings and do a dry fit with the dome in the shell and see if one dome is able to recess into the shell more than the other. use a straight edge to check.
Click to expand...

that's exactly what I was thinking.... and I'm very afraid you are correct in having to replace it... I was wondering if i could just buy that part, or have it filled and re-cut w/ a bridgeport????

thanks...
 
K

kid4now

X-H
Location
Miami Fl
Nick,

Have you tryed lapping the head. Something has to be unevevn somewhere leaving a small gap.

If you havent already get a black magic marker and color in the entire surface of the head and domes (should work ok with removavble domes) that meet the cylinder. Then lap it on some fine grip sand paper and see where the low spots are . The marker will remain in the low spots. Do the the same for the cylinder. You should be able to lap the head or cylinder down to correct the problem.

Does the head run really hot ?



Good luck,
Brad
 
K

kid4now

X-H
Location
Miami Fl
Dam like 8 posts in one minute. SFL has another good point I think the same thing happened to steve (WCF) where he kept blowing an oring due to a damaged head shell.
 
SuperJETT

SuperJETT

So long and thanks for all the fish
Location
none
sflsurfrider said:
it sounds like the dropped sleeve caused the dome to vibrate around which ate away at the head shell. if thats the case, it will we an ongoing problem until you replace the head shell.

just 1 theory.

id take out the orings and do a dry fit with the dome in the shell and see if one dome is able to recess into the shell more than the other. use a straight edge to check.
Click to expand...

Agreed on this, unfortunately.
 
SkiDaddy

SkiDaddy

Just Havin' Fun!
Location
Orange City, FL
yamaslut said:
the issue is where the head itself mates to the dome on the upper side of the head (where the middle sized oring is at)
Click to expand...

That would be the other alternative - mill down the dome seating surfaces .015 inch or so to clean up the surface & get it "true" to the bottom of the head and, in the same setup, mill the head bottom surface & outer o-ring groove the same distance. That way you could use off the shelf domes. There's plenty of material to do this.

I definately hear ya on the cost Nick - I was thinkin' if you didn't have free access to a mill maybe you could sell the current head to someone like Tricky (who has a mill in his garage & knows what he's doing) for like maybe half the price of a new one.

I found mine brand new w/domes for $350 here in Florida.:sneaky:
 
Matt_E

Matt_E

steals hub caps from cars
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Location
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FWIW, I don't think the torque values ADA gives are enough.
I torque my girdle nuts to 32ftlbs.
 
S

sflsurfrider

SkiDaddy said:
That would be the other alternative - mill down the dome seating surfaces .015 inch or so to clean up the surface & get it "true" to the bottom of the head and, in the same setup, mill the head bottom surface & outer o-ring groove the same distance. That way you could use off the shelf domes. There's plenty of material to do this.

I definately hear ya on the cost Nick - I was thinkin' if you didn't have free access to a mill maybe you could sell the current head to someone like Tricky (who has a mill in his garage & knows what he's doing) for like maybe half the price of a new one.

I found mine brand new w/domes for $350 here in Florida.:sneaky:
Click to expand...

that sounds like itd work. BUT USE NEW DOMES afterwards.
 
Y

yamaslut

Guest
Ollie Rastabean said:
Hey Nick.

I think your problem might be in the cyl. Have you put a straight edge across the top to make sure erry-ting is on the level?? New domes should have fixed that prob you were having.

-O
Click to expand...

the cylinders are ok... except for the spot where it seemed to wear down
 
Matt_E

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
No worries about that higher torque. A few of builders will tell you the 25 ain't enough.

I had mine rattle loose at 25ftlbs before.
I do the girdle nuts to 32, head bolts to 24.
 
Y

yamaslut

Guest
thanks for all the input... After I snap some pics tonight it will be more clear what to do...
 
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