Hi,

I have a FZR400, VIN=4DX001177
I need to repair the fork since oil is leaking + fork spring check, and I do not know which year for my bike! It has been imported and I do not have the year of manufacture.

=> Do you know which year for this VIN?

I have Service Information for '91 and also for '92.
For '91 model, oil capacity is 433cm3 with fork spring min free length is 354mm, oil level 106mm
For '92 model, oil capacity is 509cm3 with min free length is 341mm, oil level 80mm
So I don't want to mix up between both!

Thank you for your help

The 4DX was the UK version of the 3TJ essentially. It's not an import. It'll be between 1991 and 1995 if memory serves.

Thank you MadMotoUK
Sorry, actually I am in France, that is why I said imported
I need to know if it is '91 or '92 because fork specifications are different (oil capacity, spring service limit, ...)

I have found on the Yamaha Website: https://www.yamaha-motor.eu/gb/en/servi ... catalogue/#/
It is year '92, Model 4DX2, Silky White
For those who might need

Ah, you're in yellow jacket land, I didn't realise.

According to all my available data (my mate at Yamaha is on holiday), the 4DX is essentially a 3TJ SP model with the added bonus of an oil cooler and mph speedo. Therefore you should be looking at 433cm3 of oil. Your spring free length should be around 359mm give or take a few mm.

Many thanks! (No more yellow jackets on saturday hopefully :D )

The 4dx is the 3tj RR version not the SP, the forks are different.

509 cm3
10w
80mm air gap from the top of the inner tube when compressed without the spring.

Thank you Evilchicken0! I bought Wilbers replacement fork springs (Wilbers Promoto progressive) and air gap is 140mm. One of th existing fork springs was at the service limit (341mm)and the other one was longer (345mm)... Now everything is assembled with new damper rod bolt, slide metal, oil seal, stopper ring, dust seal and O-ring for the cap bolt ! Just need a try when rain will decide to stop
You can see on the picture I positioned the inner fork tube a bit too high, so I reduced a bit with the top of the handle crown to 4-5mm.
Just before front wheel mounting: http://400cc.fr/wp-content/uploads/2021 ... scaled.jpg

I doubt dropping the forks will make much difference to the feel because you've done a lot to the bike overall.

It's looking nice

I was thinking about Matris cartridges
https://www.matrisdampers.com/en/prodot ... t-en/f15k/

Nice! I did not know it was possible to replace all of these parts with a full new damper and rebound units! I cannot see any product for FZR400: can you install FZR600 or FZR750? Probably very expensive , but required for race (I am not, just a 400cc collector :D )