Horizons Unlimited - The HUBB

Horizons Unlimited - The HUBB (https://www.horizonsunlimited.com/hubb/)
-   Yamaha Tech (https://www.horizonsunlimited.com/hubb/yamaha-tech/)
-   -   NEED 1995 3UY Head or Cross Reference to alternate (https://www.horizonsunlimited.com/hubb/yamaha-tech/need-1995-3uy-head-cross-71588)

xtphreak 5 Aug 2013 01:13

NEED 1995 3UY Head or Cross Reference to alternate
 
Hi All

Been busily putting miles on my Tigger, but now I am getting back into my old XT.

I need a head for my 1995 3UY, the top motor mount is broken!!

I don't want to swap just the rocker cover as the cam bearing surfaces are machined in the head & cover as a matched set.

Unless I have to, which will mean a trip to a machine shop to line hone to match.

Is there another year's head I can swap?

I only see 80's heads on ebay, never a 90's.

Any help is better than none, thanks

ssbon 5 Aug 2013 08:28

hi if the rest of the head is good why cant you have the piece welded back on? or build up with weld and machine to size? got to be a better way (and should be way cheaper) as a head with a known history is always the best option ,hope this helps steve

ssbon 5 Aug 2013 10:02

hi again can you post some pics of the damage? if you go down the welding route I would bolt the rocker cover and head together to stop the cover warping with the heat of the welding hope this helps steve

Jens Eskildsen 5 Aug 2013 12:16

Wow, how did this happen?

+1 on trying to get it welded back together.

xtphreak 5 Aug 2013 16:01

Hi guys

Welding was my first thought, I hate to admit it, but the head was broken when I bought the bike back in 2000!

The frame was discovered to be bent almost as soon as I got home with the bike (after a 900 mile drive to get it).

The broken motor mount was discovered as I moved everything to a 1990 frame I had shipped to me.

I have a good welder available, he specializes in exotic bike work, like squeezing a 600 Grizzly 4 wheeler motor into a Yamaha TRZ250 because the owner wanted to race in a 4 stroke class, rewelding the heads on the TRZ and machining them back to shape

Anyway, he TIG welded the right cylinder head motor mount back on my Tiger after I hit a deer in 2010 and had to swap frames (common theme for me??)

I just thought that if I could buy a complete head assy, I could replace it myself at leisure. This way involves scheduling during my off time etc etc.

As to pics, well you see I'm currently in Prudhoe Bay, Alaska at work and my thumper is at home in the North Carolina mountains about 4500 miles away.

I tend to think of things I need to buy while I'm up here so I can put my off time to best use.
Optimization of Free Time.

Besides it gives me something to do in my off hours up here.

I guess I'll call Ed when I get home.

thanks guys

jjrider 8 Aug 2013 02:21

I'm 99% sure the '84-'89 heads will fit on your bike. It's the bottom that changes because of adding electric start(longer crank, starter mount boss on right case, starter idler gear shaft boss on left case, starter gears and room for one-way bearing in alternator cover. The rest is the same, so if you find a good set(head and rockers/cover) you can go that route.

xtphreak 28 Nov 2013 21:40

Quote:

Originally Posted by jjrider (Post 431931)
I'm 99% sure the '84-'89 heads will fit on your bike. It's the bottom that changes because of adding electric start(longer crank, starter mount boss on right case, starter idler gear shaft boss on left case, starter gears and room for one-way bearing in alternator cover. The rest is the same, so if you find a good set(head and rockers/cover) you can go that route.

Sorry it's been a while since I posted this thread.

thanks jjrider, that's exactly what I wanted/needed to hear before buying a head/rocker cover set

Bobmech 28 Nov 2013 22:18

At some stage the heads were changed to accommodate an extra head bolt, but can't recall what year?
Hopefully someone will jump in and confirm the year of change.

jjrider 28 Nov 2013 23:28

As far as I know there isn't a difference other than the decompression shaft taken out on the right side, and that is just a plug that can be taken out of the '95 cover and put in a late '80's. I have both versions on my bench right now, I will have to see about verifying this. The change may be from later versions not imported to the US.

XTphreak, what letters are cast into the cylinder base(left side) and the head, Left rear, 3AJ00 or 1jk00(cylinder) ?

steveloomis 29 Nov 2013 04:54

Quote:

Originally Posted by Bobmech (Post 445186)
At some stage the heads were changed to accommodate an extra head bolt, but can't recall what year?
Hopefully someone will jump in and confirm the year of change.

I believe it was 1988 for the US Xt model....

jjrider 29 Nov 2013 06:28

Ahh, ya, the '88 has the change, I've had an '89 apart and some of the '88 but not any of the '84-'86's yet. They both were the same as the e-starts. I looked at the oem breakdown and there is a bolt that suddenly appears on the 88's.



EDIT : I looked at my cylinders and a couple heads I have, the extra bolt added to '88 and '89's is on the end of the cam chain tunnel. The old heads will still bolt on without any modification and as long as a good gasket or/with gasket silicon, I doubt any leak will be a problem. The bolt must have been added just to help the end from seeping oil not really a structural addition.


All times are GMT +1. The time now is 07:52.


vB.Sponsors