How to fit the 600 into the 3tj

[Evilchicken0]

Not sure about the thundercat but with the 400 you have 2 wires coming in and two going out - the switch just joins and breaks the wires.

[plodder]

If you want engine allignment when using the 6mm thick mounting plates then you have to grind 6mm off the left hand side cylinder head mounting points. If you don't then the frame will twist. Many have done it without modding the mounts and they still work but not something I would do.

[nick]

I'm planning on maching the mounts on the left to make room for the plate.

Can anyone confirm the issue with the sprocket alignment? As a refresher i've got a t'cat motor in the 3tj frame.

After a LOT of searching, it appears that the ouput shaft is longer on the cat than the foxeye so the front sprocket sits out by about 8-10mm (not done an exact measurement, just know that its significant).

It would seem the only option is to space out the rear sprocket...........

[Evilchicken0]

I haven't heard of that before.

[cagiva996]

just checked 4jh and thundercat part nuimbers and theyre the same 4TV174210000(t/cat) 4JH174210000(foxeye fzr600r) though it is strange that the t/cat output shaft isnt designated as 4jh if its exactly the same part so there may be a grain of truth somewhere,but im still sure its the same part.perhaps the 4jh runs a 520 pitch sprocket instead of 530 like the t/cat but again the part numbers for the sprockets are the same bar the 4tv/4jh designation,ill check if i can.have you got the motor in and bolted up with the adapter plates,mine didnt look like it was going to line up til everything was in place and done up.

[nick]

The two rear mounts are in and torqued. On the left hand side the cylinder mounts are kissing the frame, on the right there is a 6-7mm gap. Like this, the front sprocket is about 5-6mm over to the left.

After much deliberation and talk of twisting the frame by trying the squeeze the plate in, i'll be griding 6mm off the left cylinder mount to fit the adapter plate.

Aside from that, i cannot see how the engine would move the 5-6mm to the right to accomodate the sprocket alignment as there isn't the 'play' in the rear mounts. I had my doubts when i had both the 400 and cat motors on the garage floor, as a quick measure confirmed the difference in the widths. It's a crude diagram, but as you can see there is a difference in the relative position of the sprocket versus the engine mount



I'm using a 520 chain and sprocket, but as i measured from the centre line of the chain run, the 'thickness' of the sprocket matters not.

So, do i have a unique problem that no one else has encountered, or am i being really blonde and missing the obvious?

[cagiva996]

this thread is very interesting.are you using a 3tj or a 4dx frame,as my second hybrid build with a 4dx frame came to an abrupt halt(after id had the frame powdercoated satin black ) when i discovered that the motor (t/cat) wouldnt fit in the frame so i assumed the frame was bent,although it had no damage.i know people have used 4dx frames for hybrids but its just a thought.i didnt have to grind anything off the frame it did just slot into place with no chain run issues.

[Evilchicken0]

I know the T'cat and Foxeye use a wider rear wheel with the same 160 section tyre, but I always asumed the difference was taken up in the tollerance rather than moving the sproket out.
've got a 4JH engine sitting in the garage I could have a look at it for you if want .... although Significant Other wants me to jobs around the flat so it might not be so quick.

[nick]

.....are you using a 3tj or a 4dx frame

4dx

Wasn't aware of any differences between the 3tj and the 4dx frames........

Boris - if you can have a look at your 4jh engine that would be handy. I'd be interested in the measurement as shown on my (crappy) diagram

[cagiva996]

there are some differences between 4dx and 3tj/3tj2 frames but i always thiought the dimensions were the same.the 4dx frames have a slightly different finish and the holes in the frame spars where the loom passes thru to the headstock is an open hole instead of the 3tjs welded in ally tube.i only realised this when i was prepping it(4dx frame) for powdercoating but i was always sure all the dimensions were the same for both models.the t/cat motor wouldnt fit between the frame spars with the engine mounting plates attached to the motor so i assumed it(4dx frame) had been in an accident andf been bent at some point.the only thing ican think of is that the 4dx frame may have been different for the uk and france.french frames have the prefix 4dx2 and the european is prefixed 4dx1.i think most 3tjs and 3tj2 were built in 89 and 90 and were only for the jap home market its not entirely impossible as the 4dxs wernt officially imported to the uk til 92 or 93,that there may have been some differences between the models for the jap and european models (cost cutting) as the fzr400 cost nearly 6 grand in the early nineties.i know this aint gonna help you fit the motor in the frame but your problem has intrigued me.i really hope you get it sorted.ive got a scabby sp frame you could borrow if you want!