Building Big Bore FJ1100

[Flying Scotsman]

I did a test fit 1250 motor head and cam cover fits in the frame.

I think I need to buy a sprocket  cover/clutch slave mount as my 1100 cover wont fit.Anybody have a xjr1250 cover for sale.I found one on ebay but its big $$.I need a couple of c/c bolts too there a diferent size than the 1100 /1200.I think it was #32 and #34 I need.So I need 2 cc bolts and I think I need a xjr 1250 sprocket cover and bolts to make this work.

Heavy engine to lift up onto the workench by yourself.

Posted by: racerman_27410 
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Randy,

I happen to have a complete 1250 engine in my 86 frame.... granted  it is tight, and there is a trick to getting it in place but no modifications were required to fit it other than modifying the chain cover.

What did you do to the chain cover ?

Posted by: racerrad8 
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Like Chris said, the head oiler is not needed and will not fit without major modification as it will hit the frame.

You do need to make sure the internal oil passages have not been blocked off on that head you are planning on using which is a common practice by a lot of engine builders.

How do I check this.

[racerman_27410]

the rear "ear" has to be cut off the chain cover in order to clear the frame.

no big deal.


also make sure you have the 1250 clutch pushrod (its longer)


Kookaloo!

[Flying Scotsman]

the rear "ear" has to be cut off the chain cover in order to clear the frame.

no big deal.


also make sure you have the 1250 clutch pushrod (its longer)


Kookaloo!

I have the longer pushrod and an extra 1100/1200 cover I can modify.
You are using a 1100/1200 cover not a XJR1250 cover then.

[racerrad8]

1) I think I need to buy a sprocket  cover/clutch slave mount as my 1100 cover wont fit.Anybody have a xjr1250 cover for sale.I found one on ebay but its big $$.I need a couple of c/c bolts too there a diferent size than the 1100 /1200.I think it was #32 and #34 I need.So I need 2 cc bolts and I think I need a xjr 1250 sprocket cover and bolts to make this work.

You do need to make sure the internal oil passages have not been blocked off on that head you are planning on using which is a common practice by a lot of engine builders.

2) How do I check this?

1) I guess I am confused about the direction you are going. I thought you were transferring over the top-end parts to your 1100 bottom end. If you are using the 1250 lower end then you will need the 1250 sprocket cover. I do have them brand new and you will also need the five bolts, bearing and two seals for the shift shaft. Email me if you want me to get pricing for you and like Randy T stated, it will need to be modified just like axiom-r did on his R1 swingarm install.

2) With the head off the engine, turn it over to be able to see into the left side stud/dowel holes. Each hole will have an angled hole that supplies the oil the the cams. If it is plugged, then there is usually a 1/4" set screw installed in each of the holes.


Randy - RPM

[Pat Conlon]

You do need to make sure the internal oil passages have not been blocked off on that head you are planning on using which is a common practice by a lot of engine builders.
With the head off the engine, turn it over to be able to see into the left side stud/dowel holes. Each hole will have an angled hole that supplies the oil the the cams. If it is plugged, then there is usually a 1/4" set screw installed in each of the holes.

Randy - RPM

Randy, why would an engine builder do this? To increase oil pressure? Then how would oil get to the cams? External oil lines like a Hank Scott's oiling system?

I think I just answered my own question.....carry on....

[Flying Scotsman]

Im using the 1250 motor in the 1100 frame.
So i cant mod the 1100 cover to work.I was going to try and remove material on the inside to get it to fit flush till I could get a 1250 cover.

you will also need the five bolts, bearing and two seals for the shift shaft.
What 5 bolts bearing and seals ?
I do need 2 c/c bolts.Located at the left rear of the engine are 3 large cc bolts I have the middle one im missing the other 2.

What it looked like to me was that I need  a 1250 cover and bolts as the 1100 cover was to narrow and wont clear the sprocket or fit flush to the c/cases.

you will also need the five bolts, bearing and two seals for the shift shaft.
What 5 bolts bearing and seals ?
Why do I need them ?
Dont I have them in my 1250 cases already ?

im glad I looked online before heading out to Palatine to cut up a cover .

[racerrad8]

From reading the others past experience you will not be able to remove enough material to make the 1100 cover work.

When you install the 1250 cover, you will need all of the associated hardware to make it work. (five bolts, one bearing & two seals) Since you do not have the cover, yes you will need them and no your 1100 cover does not have them. The 1250 cover is 8mm wider and requires the longer bolts to mount it, and your 1100 cover/slave bolts will not work.

The other two crankcase bolts at the rear for the block are no problem, I have plenty of those.

Randy - RPM

[racerrad8]

Randy, why would an engine builder do this? To increase oil pressure? Then how would oil get to the cams?

They use two reasons...

1) To get the oil to travel to the head externally to keep it cooler so it doesnot absorb heat traveling through the engine.
2) To increase oil flow (not pressure) to the head.

There is a minuet basis of #1.

#2 is just a selling point unless there is modifications done to the to increase the flow within the head.

And I can tell you, that in all of my years, I have never had a head in my hands from another engine builder that had this modification completed. It is something I do to all of my engines wether they are externally oiled or not.

Randy - RPM

[Flying Scotsman]

Randy
I need the parts but im still not sure what seals bolts etc I need.Can you help me order the right parts.

[racerman_27410]

[quote author=Flying Scotsman link=topic=5261.msg48552#msg48552 date=1323963639

I have the longer pushrod and an extra 1100/1200 cover I can modify.
You are using a 1100/1200 cover not a XJR1250 cover then.

[/quote]


nope i am using the complete 1250 engine including the sprocket cover..... you have to use the 1250 cover on the 1250 engine as the output shaft/shift shaft and clutch pushrod are all longer than the stock FJ engine.

KOokaloo!

[Flying Scotsman]

Thanks for being patient guys.
Randy said he had the parts I need so I will go ahead and order from him.
I need a c/c filter as well.

[racerman_27410]

Thanks for being patient guys.
Randy said he had the parts I need so I will go ahead and order from him.
I need a c/c filter as well.

are you already running a wider rear wheel?   Might be a good time to think about it.

the output shaft on the 1250 engine will allow you to easily run a 5.5 inch rim with a 180 rear tire without having to worry about spacing out the C/S sprocket. (the XJR uses these sizes)

if you are still running stock wheels then you are going to need to space out your rear sprocket in order to get a straight chain run.


KOokaloo!

[Flying Scotsman]

I was wondering about the sprocket offset.
Do you know what the difference is in inches or mm.
Could go either way with sprocket or wider rear wheel I will have to read up on it.Saying that my 85 1100 sits nicer for me (im short) and rides and handles better than my 90 1200 on stock wheels.My old bias ply Dunlop 501 is wider than the Michelin Mcadam on the 90 as well.
85 rides awesome even has antidive.If I put a different rear wheel on and mess that up it would suck though.

[Flying Scotsman]

Randy I sent you a email.I need to talk to you so I can order some parts.
Scott.........

[Flying Scotsman]

Contact made thank you Randy