swapping heads

greetings everyone : ok i have a1980 kz1000G converted to carbs, was in the middle of changing the head gasket when i found that the PO had used 3 wrong bolts on two different cam caps . as i removed them one broke off the other two stripped out. i could try fixing it or i have a 76 900 engine that i could use the head . if it will work . it looks like it will bolt up the same. my question is is everthing the same functionally and clearance wise. rlcarter

little different cams....more teeth on the the crank...you have MKII in the 80..get a 79 head...or machine shop to fix it...the broken one can be a hassle...tad different..not exact swap...not 100% though.....might just need to swap cam sprokets from the 80 the the other cams....then it is a direct...smaller dia exhuast studs too but that is no big deal..just use the right nits...

as far as timing--same---as far as piston hitting valves.no.....make sure you get it right and check the clearnaces..

do i have to use the cams from the 900 and switch cam sprockets or can i use the whole camshafts from the 1000

There are a few things to consider when thinking about switching heads. Do you know the condition of the 900 head? Valves, valve guides, valve guide seals? Have you seen the 900 motor run? The 1980 model valve cover is diffrent and do you want to change the original head. If your not worried about keeping the motor original or mix matching then no big deal. Also has the 900 head been on a shelf or is it still on engine? As far as the swap goes, it is a direct bolt on. I would mic the cams and use the ones with the most lift and in best condition. You will need the 32 tooth cam sprockets and 6mm exhaust nuts. Be sure to double check your valve clearance. Good luck hope this helps. Dave

Repair with time-serts may be a feasible option.

Good Fortune!

thanks for the info dave ; patton ; and trianglelaguna ; just got back to the garage. the 900 head has been on an engine sitting for about three years and i just noticed it has two broken exhaust studs so both heads will need repaired. in that case i think i will stick with the original thanks again

I was going to say, the valves are a little smaller on the 900. The cams have higher lift but not enough to buy and make a switch. If on hand why not. Both should have new valve seals if been sitting or old. They dry out and foul plugs. Fixing a few bolts is the way to go. IMO
Steve

rlcarter wrote: ...900 head...has two broken exhaust studs....

Sometimes easily replaced.
Heating with a butane torch should relax the thread grip.
Turning the stud depends on ability to grasp it (if there's a sufficient protruding portion) or weld a nut onto it to grasp (if the stud broke more or less even with the head).

Good Fortune!

I worked at a motorcycle shop for many years and used to extract broke off bolts all the time. I will share with you what I learned to be the best method. Lets say the bolt is broke off inside were you can't get any vise grips or anything on the bolt to remove it. This is how you do it. Get you a spring loaded center punch. Place the center punch in the center of the broken bolt. Make an indentation in the center make sure its a good one may need to do it severel times. Just be sure your in the middle of the bolt make a good indention. OK, now buy a drill bit kit with a bunch of diffrent sizes. Start by using the smallest bit first. Use the indentation as your guide. Make sure not to drill to deep. Also do not put to much pressure on the small drill bit as it will break. Apply a small amount of pressure and let it do the work. Drill down until you feel like your at the bottom of the bolt or close to it. Then go up one size on drill bit. keep doing this you will get close to the threads but before it gets there bolt will give away usaully just coming out while drilling. At the same time making sure not to hit the sides of the threads. When you take out the middle of the bolt the "core" it will then just come out on its own very easy. I dont use easy outs because if you break that off in a bolt your almost screwed at that point because the easy outs are made from carbide and its almost impossible to drill into. Once you have taken out the core its like a knife going through butter very easy. The whole key is drilling straight down center of the bolt. That is probably the hardest part of it all. After I make a indention I start out very slow drilling just a few seconds I do this over and over to make sure drill bit is going straight. After you got it going straight its all down hill from there just a little time. It usaully takes me about 20 to 30 minutes to extract a bolt. But I'm not trying to see how fast I can get it done just have a really good method. Sometimes after I drill the center ""core" out I will use a extractor. But usaully it just comes right out on its own. I hope this helps. Dave

That's using reverse bits right? I use cutting oil whenever I drill anything. I just dip it in and the oil helps cutting and preserves the bit. Hell you learned that in shop didn't you Steve? :laugh:

Ive extracted hundreds of bolts and never used cutting oil :whistle: however ive never worried about preserving my drill bits either. After ive used them quite a few times I just toss them out and get new ones. The drill bits i use are not all that expensive maybe 20 bucks for a set i use them 5 to 10 times and thats it. maybe i should invest in expensive drill bits and cutting oil and try to preserve them. :dry: