FJ 1100 motor into XS11 frame ?

[Wildkat]

We would probably go with pod filters

I'm already going to pod filters so this will be done before anything else anyway...

I think it would be less work to add normal handle bars, seating and foot pegs to a FJ1100 than to put a FJ engine in an XS frame.

But not nearly as much fun...
The idea for doing this is to have the styling of the XS with the power of the FJ... Kind of a home made XJR... Not certain I would get that if we were to use the FJ frame... but since we just started kicking this idea around... I'd have to look more closely at everything...

In exchange, I get to ride the final product

John barely gets to ride the FJ... okay... so the fact that it's out of commission 75% of the time might have something to do with that...

The one thing I found hard to do on a FJ1100 was not blowing away the national speed limit.

This seems to be a common problem with these bikes.... must be a factory issue?


The idea of combining the two bikes has opened up a world of possibilities... I wanted to play with the exhaust on the XS project bike... but now possibly putting the FJ engine in it will change up all previous ideas... Since we're basically working with a blank slate... I'd like to get as much performance out of the stock FJ engine as possible...
Any thoughts on exhaust systems to help attain this goal?

[madmax-im]

Whoa Nelly!

A homemade XJR?!That would be awesome.If this bike came my way I snatch it up like nobody's business!But short of a real XJR1300 a "replica" bike would prolly be just as niceMakes me wish I still had my FJ1200

[fredintoon]

Let's be careful out there.

Hi Wildkat,
the stock XS1100 already has ~20% more horsepower than it's cycle parts can safely cope with and you propose grafting in the even more powerful FJ1100 mill? I do hope and trust you will be making significant upgrades to the XS1100s cycle parts to match all that extra power. I'd hate to read that you had become a smear of forensic evidence.

[Wildkat]

I'd really hate to read that too, Fred



No worries... I plan on doing my homework before I do ANYthing to either bike... It's hard enough to think about taking my beloved FJ apart... but I REALLY like the idea of the possibilities of this project...

Other than the frame and cosmetic bits... I wonder how many of the XS parts would be usable anyway... or were you talking frame as well?

Ben... yeah... I fell in love with the XJR the first time I saw it... It's the best of both my worlds combined... and it looks AWESOME!!

[FJ111200]

I've taken my beloved FJ apart, and this is what i've started. It's an XJR1200 frame, etc, but using an FJ engine, wheels forks. I'll put a few more photo's on soon. It's come on a few steps since these photo's but these are the ones i've got so far.

[Wildkat]

Now that's cool!

What kind of mods are you having to do to get this to work?

Wish I had the chance to get an XJR frame... with an XJR engine... and cosmetics...

[FJ111200]

The main problem was that the FJ drive shaft is shorter than the XJR, and with using FJ rear wheel aswell i had to space out the wheel. And the gear change shaft is shorter aswell, so i had to modify that to stop it hitting the lower frame rail.
Can't you import a frame from UK or Europe?


It's still in the experimental stage at the moment. Those old XS shocks are going to go, they are to short and tighten the chain to much when on both wheels.
I got a bit sick of the FJ frame, as there is not a lot that can be done by the way of customising.

[Wildkat]

Maybe...

but the cost might be prohibitive... plus getting the other pieces (seat, side covers, etc) to fit would be another problem that I'd like to stay away from...
By using the XS frame, I'd like to be able to keep the cosmetic bits... basically keep it looking like an XS... but with more power...

Because the whole idea is so new... I'm still looking at possibilities which seem endless at the moment... so importing a frame wouldn't be out of the question...

I'm interested to see how your project turns out...

How difficult was it to get the engine to fit into the XJR frame?

[FJ111200]

The XJR engine is the same as the FJ, and so is a straight swap, just the driveshaft is different. The FJ12 was a bored out 11, and the XJR13 was a bored out 12. I'm led to believe the XJR and the FJR1300 use the same shaft. There is some differences with the carbs, and the standard XJR12 is down on power compared to the FJ12. FJ forks are 41mm and XJR 43mm. Wheels are 17in front and rear on the XJR, 17in front and 16in rear on the FJ12. The FJ11 uses a 16in front. As i said, i'm using the FJ12 forks and wheels set - up.

Like fredintoon says, watch out for the power upgrade if you go down the FJ in XS chassis and running gear.

[xschop]

The main problem was that the FJ drive shaft is shorter than the XJR, and with using FJ rear wheel aswell i had to space out the wheel. And the gear change shaft is shorter aswell, so i had to modify that to stop it hitting the lower frame rail.
Can't you import a frame from UK or Europe?


It's still in the experimental stage at the moment. Those old XS shocks are going to go, they are to short and tighten the chain to much when on both wheels.
I got a bit sick of the FJ frame, as there is not a lot that can be done by the way of customising.

Do you mean the sprocket shaft is too short on the FJ for the XJR frame? If so, an offset sprocket would do the trick.....If you also spaced the rear wheel to align the front FJ sprocket, what about rear wheel alignment?........also, is the stock/factory rear wheel centerline right in the middle of the frame pivot points?......and what is the distance between the XJR swingarm pivots? This info would tell us how the FJ motor would sit in the XS frame. I think the XS frame would have to be Notched on the lower tube to allow for the chain-path just like the XS chain conversions with 180 rear tires.....

[FJ111200]

Yeah, the sprocket shaft is shorter on the FJ. I looked at an offset sprocket but declined as it was £56 and then i would have had to buy an XJR rear wheel. I'm trying to keep it as cheap as possible by using as much FJ bits as will fit. The difference between the rear wheels is that the FJ is about 7mm to 8mm narrower on each side where the bearings outer faces sit. The XJR swingarm uses a single bolt like the FJ, as opposed to the two pivot bolts on the XS. Both front and rear wheels on my project XJR/FJ are cental to each other. I didn't measure the width of the XJR swingarm sorry. All i know is that i was going to use the FJ swingarm but it was narrower than the XJR, and also the FJ has a monoshock suspension and didn't want to go down the path of aluminium welding on the FJ swingarm, so opted for the standard XJR item. I think your best bet about the FJ and XS comparison for the chain conversion would be to find an FJ lower crankcase and and XS frame and see what's what. Sorry that i can't be more specific, i should have kept records i suppose.

[fredintoon]

If you can read about it you ain't dead.

Hi Wildkat,
John's original hijack of Poorboy's post mentioned an FJ power unit, a MNS rolling chassis and a wire welder. And an MNS is just a Special in a dinner jacket so it has all of the same handling characteristics. Or lack thereof. I must admit that this elderly coward ain't got the bottle to ride any kind of XS11 unless it has a sidecar on it to calm it down.

[yamahansolo]

ok what "cycle" parts are you talking about fred?

there is a guy on here with a 211 hp turbo'd xs. i don't know what other mods he has done though but i don't think the suspesion had much done to it???

[fredintoon]

Cycle parts

ok what "cycle" parts are you talking about fred?

there is a guy on here with a 211 hp turbo'd xs. i don't know what other mods he has done though but i don't think the suspension had much done to it???

Hi Yamahansolo,
"Cycle parts":- Any of the components of a rolling chassis.
"Rolling chassis":- What's left after you take the engine & tranny out.
The guy with the turbo? He's sliding down the razorblade of life far faster than I'd dare to go.

[xschop]

XS frame

The XS frame can be stiffened up with simple gussets and/or solid motor mounts in the rear can turn the "Flexi-flier" into a solid handler. also to go a step further would be to gusset the upper dual-tube backbone and around the tree.....Take a look at what member 79XS11F (Rob) is doing.....I just have the solid motor mounts in and you notice the improved feel of the bike in hard corners right off the line.....If you stick the FJ motor in the XS frame the rear motor mounts that have to be welded in would allow for even greater frame reinforcement anyway. Whoever sticks an FJ motor in an XS frame would have one sick ride, not to mention the 180 tire that the XS is lacking, and removal of the jack-shafting action that I don't like about a stock XS11.....