engine and parts interchangeability

[bumjug]

Ok. I won't be able to work on my bikes for at least a couple weeks, so I'm hoping to get straightened out as to exactly what I have. I have a freshly rebuilt engine marked 4N9, a parts engine marked 2F0, and two non runners that that haven't even looked at that are marked 447. From the identification chart I believe the two 447s to be '76 C models, the 4N9 to be a 81 H special II. And the 2F0 bucket of engine parts is most likely from a '80 XSSG that is actually engine code 3G1.

So what have I got? My plan is to swap the 4N9 into one of the Xs650C's... Will it drop right in? I know the special frame is longer, but will the motor mounts line up? What parts are the same and different between all of these engines? If I end up with two complete strong runners out of the lot I'll be a happy man.

THANKS mateod!!

 

[fredintoon]

Hi bumjug,
the earliest XS650 in our family stable is my son's '76, the latest is my '84 and for sure, every engine will fit in every frame between those years.
Dunno if the Special II has the transistor iggy like the other '80 and later bikes or not.
Check the engine for nothin' under the points and advancer covers, Hall Effect sender on stator, Trigger magnet on rotor.
It'll need the TCI unit too.

 

[bumjug]

F yeah thanks... Put a pamco with pma on when I rebuilt the top end of the 4N9 special H motor... Anyone know if there are differences in cranks pistons bottom end etc?

 

[XSLeo]

From 74 up when they started the 447 series engines they did make a few changes on the engines. Little things like the cam chain tnsioner, breather box.
All the internal parts were the same.
The Special frame and the standard frames are the same lemngth. Thmajor changes to the frame from the standard to the special was they moved the top of the rear shock forward and down. They did this to copy the look of a Harley.
They did a few changes to the passenger peg mounts. Seats and frame side covers.
Most of the changes were cosmetic, the mechanicals stayed pretty much the same.
Leo

 

[beatnik2138]

xsLeo you are very knowledgeable! I was hoping to pick your brain. I have a 447 motor at home, in the process of tearing it down to rebuild. My old mechanic lost the cylinder head after hot tanking some parts. I will be purchasing a decent amount of parts from a guy this weekend. The motor I tore down and lost the cylinder head is a 447, the parts I'm purchasing this weekend one is 447 the other are FO2. I'm curious if the motor parts are interchangeable. Also is x4cylinder heads x4cylinders, x4cases 1transmission and 1kickstart shaft all worth 500 bucks? I believe I'm getting an almost complete motor with what I listed above. Basically im curious what motor parts are interchangeable and what aren't. I appreciate the help!

 

[TwoManyXS1Bs]

Two main things to watch out for are:

Mismatched head and camcover. Do a forum search on "match head" for more info.

Transmission gearsets. There was a change to the gear splines in '77. No interchangeability between pre and post '77 splined gears and shafts. Do a forum search on "gear spline" for more info...

 

[beatnik2138]

Ok. Thanks for the feedback!!

 

[TwoManyXS1Bs]

Need to have other more knowledgeable members jump in here, but another I can think of is the camshafts. I believe 80-on camshafts are missing the internal bushings (for the advance rod)...

 

[beatnik2138]

I'm almost positive there are no internals included with the majority of the parts I'm going to be purchasing. I'm most curious about if the 477 cylinder head that I will be purchasing this weekend will fit the 477 motor I have at home.

 

[TwoManyXS1Bs]

I believe that all 72-83 heads (with matching camcover) interchange on all 72-83 cylinders. Make sure you have the alignment dowels...

 

[beatnik2138]

What's the worst that will happen if the camcover doesn't match? The 477 at my house has everything but the cylinder head that's what I plan on taking from the 477 I'm buying this weekend.

 

[TwoManyXS1Bs]

Basically, 3 things are trying to align there. The hollow dowel pins, the cam bearing seats, and the valve cover openings. Those other threads go into more detail...

 

[beatnik2138]

Ok. Will the match head thread be where I should start?

 

[5twins]

On the front of the head and top cover, between the valve cover openings, you will find some numbers stamped. They should match if the two parts are a matched set .....

 

[beatnik2138]

Great! Thanks for the feedback 5twins! Just texted the seller all the cylinder heads and covers match!! So it would be safe to say switching the pair onto the jugs will work just fine?! Is there a major difference between 447 and 2fo?

 

[5twins]

I don't think there's any differences between 447 and 2FO stuff, other than the cam with no bushings in it (1980 and newer). I think the 2FO stuff is just a later version of the 447 stuff. There are differences on the '73 and older 256 motors. Many of those parts don't swap. So, if all this stuff is '74 or newer, you're golden. Do note the tranny gear changes 2M mentioned. I think the whole tranny will fit in any later case, you just can't mix the older and newer gears.

 

[beatnik2138]

Awwesoome! Soo stoked to get all this and finish what I started!! I'm only getting one tranny with all the stuff so the rest doesn't have any, where would be a good place to find trannys that will fit with what I have? I'll post my progress! Thanks for all the input and feed back! Much appreciated! Also is 500 bucks for all that I'm going to purchase a good deal?

 

[lakeview]

Hi Nick
No one really wants to be in a position to say what something is worth. For me, without any engine internals, I would not be paying anything near that price, but that's just an opinion, and like elbows, everyone has one or two.
How I value something is to go on ebay motors and see what others are selling the same item for. Add a few grains of salt and you may have a baseline.
The other aspect is that you would be buying stuff you do not need. Any XS650'er with more than one in the garage - hands up folks - will have a tendency to over accumulate - like going to an all you can eat buffet. While it is tempting to have extras, when both of your bikes are together and running, you may look at your extra barrels, cases, etc. and wonder what was I thinking.
Good luck with whatever action you take; it is always nice to see another enthusiast, especially with a stockish Standard.
cheers

 

[5twins]

It seems a bit much to me too for mostly empty cases. I'd offer him maybe $200 and then you could barter some and maybe meet in between somewhere.

 

[beatnik2138]

I can't stress enough how much I appreciate all the input!! I don't believe in paying more than what something is worth. Sorry for the long post but here is the ad the guy posted.

The CL ad:
A while back I bought a ton of XS650 and TT/XT/SR500 parts from the estate of a man whom I was told worked as a machinist for Boeing, which makes sense since his home was in Everett, was an amateur gun smith, and raced flat track; the shop behind his house was a fully outfitted machine shop.
I picked up a lot of great parts, sold some, and am keeping all of the Yamaha 500 stuff, these engine parts are everything I have left for the XS650.
The gentleman clearly knew what he was doing, unfortunately I didn't receive any paperwork or documentation, and thus have no knowledge of exactly what has been modified or why any of these motors were torn down.
All of the parts look to be in good shape, I haven't found any damage/flaws/etc, but they're dirty/dusty from sitting in his and my shop for quite a while
Everything I have is pictured:
4x cylinder heads
4x cylinders
4x cases
1x transmission
1x kick start shaft
One cylinder is sleeved and bored out to 83mm. The bore is in good shape with cross hatching still visible and no distinguishable wear/damage when I run my nail along the bore, a hone is likely all it will need. As for what pistons he was running, I have no idea, but do know that VX750 sleeves and pistons are 83mm and have been made to work. One set of cases has also been bored out to accept the sleeved cylinder.
The other two cylinders are without sleeves and have been bored out as well.
The 83mm cylinder and matched cases will save some considerable cost and machine work for someone looking to build a big motor.
Let me know what time on Sunday I should expect you… where are you coming from?
I’m about 3 blocks from exit #253 on I-5.
Thanks.