Engine re-build advice

[jscgdunn]

Hi Everyone,
We are going to rebuild an engine and a we are starting with a basket case 1100.  Our assumption is that except for the change in bore, all the internals are the same between an 1100 and a 1200....so please correct us if we are wrong!  We would like to build a stock 1200 engine from this pile.

1) The head: The head we received is a "1200 head with only 5,000 KM".  However, it has some damage on the face of it from being handle and transported.  It looks like the damage can be "shaved" out, however, I ahve not been able to find much info on how much can be removed.  Any advice?
2) Jugs: we have the 1100 jugs, Can they be bored to 1200 specs?  If not is it better (ie cost wise) to start with 1200 jugs or to get them resleeved?

Probably have some more as we go.....

[JMR]

-.005 should clean up most problems. I have personally taken off more than .025.

[FJmonkey]

Hi Everyone,
We are going to rebuild an engine and a we are starting with a basket case 1100.  Our assumption is that except for the change in bore, all the internals are the same between an 1100 and a 1200....so please correct us if we are wrong!  We would like to build a stock 1200 engine from this pile.

1) The head: The head we received is a "1200 head with only 5,000 KM".  However, it has some damage on the face of it from being handle and transported.  It looks like the damage can be "shaved" out, however, I ahve not been able to find much info on how much can be removed.  Any advice?
2) Jugs: we have the 1100 jugs, Can they be bored to 1200 specs?  If not is it better (ie cost wise) to start with 1200 jugs or to get them resleeved?

Probably have some more as we go.....

Check with Randy at RPM, he is a builder and racer and one hell of a guy......
http://www.rpmracingca.com/

[jscgdunn]

Monky,
thanks....yes hoping Randy will chime in for benefit of all.

[Flynt]

2) Jugs:  Any advice?

Massage thoroughly with oils or whatever else you might like.  Not everyone has jugs you know... be sure to recognize your luck!

For your engine questions, we're all going to wait for Randy to weigh in...  he's the man.  I think you'll want XJR "jugs" though...  they are a couple hundred cc's bigger to start with.

Frank

[FJmonkey]

Massage thoroughly with oils or whatever else you might like.  Not everyone has jugs you know... be sure to recognize your luck!

For your engine questions, we're all going to wait for Randy to weigh in...  he's the man.  I think you'll want XJR "jugs" though...  they are a couple hundred cc's bigger to start with.

Frank

Frank, Frank, Frank..... I got nothing.... as you were .......

[yamaha fj rider]

2) Jugs:  Any advice?

Massage thoroughly with oils or whatever else you might like.  Not everyone has jugs you know... be sure to recognize your luck!

For your engine questions, we're all going to wait for Randy to weigh in...  he's the man.  I think you'll want XJR "jugs" though...  they are a couple hundred cc's bigger to start with.

Frank

Those are some big jugs. 

Kurt

[andyb]

I'll avoid the sidetracking...

Off the top of my head, internal differences aren't vast.  The later shift forks are the ones to use, but apparently they've superceeded all the numbers so you'll be okay there (just fit new ones, they'll be longer than the old ones if they're correct).  The ignition system was changed at some point as well, so the pickup triggers look different and I understand they went from TDI to CDI in the later ones.

Shaving the head to clear damage should be fine, go too far and you'll start hitting the valve seats, so that'll give you a rough look at how much meat is there.  A thicker base gasket can make up the difference as needed so you can set squish to where you want it.  Take a picture of the head if you want/can?  So long as it ends up flat and level, and doesn't have damage between cylinders, a ding from shipping shouldn't be a big problem depending on where it is.  For reference, the gasket that Randy supplies is 0.010 rather than 0.020, so the piston/head+valve distances will change slightly.  As with anytime that you're shaving the head, measure carefully your clearances.

As far as your barrels, according to the Wiseco catalog, taking the 1100 (74mm) to 1188cc (1200 spec, 77mm) requires a rebore only.  Once you go into the 78mm (1219cc), 79mm (1250cc), or 81mm (1314cc) range, new sleeves will be required (or a set of cylinders from a 1200, which would just need bored).  The XJR1300 (1250cc) apparently has a slightly different design, something about siamesed sleeves, but that shouldn't come into play for you unless you're going significantly bigger.

While you're in there, you'll want to do the usual stuff and make it a "new" engine:
-main and rod bearings
-starter chain + guide
-camchain
-various gaskets and seals, particularly the valve cover grommets, head and base gaskets
-new late-model shift forks
-rings, circlips, pistons (a 74mm piston doesn't seal well in a 77mm bore...)
-4-brush starter
-clutch spring (or coil conversion, or two springs) along with new frictions if needed, but you'll find out once it runs if it slips

I'm probably forgetting things, I'm tired.  Call/email Randy and he'll get you going on the right path.

[JMR]

Only thing I'd add is if you are milling the head and using the .010 base gasket think about using slotted cam sprockets.

[racerrad8]

Okay, as already stated the difference are few between the generations of the FJ through the XJR. The cylinder design & bore size being the biggest difference.

Yes, you can bore the 1100 to the 1188 standard bore of the 1200, but that is all there is.

From the you need a set of 1200 cylinders which will allow you to go as big as 1219cc.

From there you will need the 1250(1300) cylinders to go any larger on the bore. The1250 cylinder is a siamese cylinder, meaning there is no air gap between the cylinder pairs. So, there is some reduction of cooling of the cylinder pairs, but the bores are much more solid. This cylinder is not required for anything above 1219cc and not recommended to sleeve back smaller.

The connecting rods, shift forks, two bolt alternator, several different size case bolts, shorter case studs & nuts, starter clutch, ignition pick-up & rotor, barrels & pistons, clutch cover/ventilation system and I am sure there other I am forgetting from the top of my head but that is the majority.

If you are going to the 1200 bore, I recommend getting a 1200 cylinder as a starting point and then determining your plan of attack from there.

Randy - RPM

[SlowOldGuy]

One other thing to keep in mind.

If you go above 1188 and need new liners, "I think" you'll have to get the cases notched to provide clearance for the new liners.

DavidR.

[racerrad8]

One other thing to keep in mind.

If you go above 1188 and need new liners, "I think" you'll have to get the cases notched to provide clearance for the new liners.

DavidR.

Case clearance is only required for sleeves fitted for 1219 & higher.

Randy - RPM

[fj1289]

Randy - how does the cost of sleeving the 1200 cylinder block out to 1314 cc compare to buying an XJR cylinder block and taking it out to 1349 cc?

The 1349 pistons look like a much nicer more modern design (lighter & less drag) than the old 1314 pistons though...

Chris W.

[jscgdunn]

Thanks everyone for all the advice.  Will update as we move along!

Jeff

[skymasteres]

Does anyone have any info on clearancing the upper crankcase with the 1349 kit?