Yamaha xs 400 dohc

[Fred]

Hello everybody,

My name is Frédéric, i'm from belgium.
I'm an Airplane technician for the belgium militairy. But my passion is bike's.
Just finished my first project ever.

It's à yamaha xs400 12e dohc.

I rebuild the engine and respray'd everything. I changed all the bearings and tires. I have documented the complete disassembly and assembly.

I'll post pictures asap.

Just have 1 issue left, and that's when i change gears, up or down is the same.
The engine pulls to the left...
Do i need to adjust the clutch? Or is my problem elswhere?

 

[drewpy]

nice bike, check your rear wheel alignment and then check your fork to see if they are bent or twisted.
can't think of any other reason for it to slew to one side

 

[Fred]

I'll rechek the fork and the alignment. But the strange thing is when i Let the steering go while driving, the Bike go's perfectly straight. It only occurs when i shift...

 

[16VGTIDave]

Did you replace the swing arm pivot bearings? They are often forgotten and in poor condition.

 

[Fred]

Yep i replaced them to because they were indeed in very poor condition.

 

[MrStubb]

Sorry to say but I don't think your transmission would cause your bike to veer either way. My first thought is your swing arm bushings but they've been replaced. Is it at all possible that there's a hidden crack somewhere on your rear swing arm or rear pivot point that would open up some on acceleration?? Possibly a broken weld?? I'd also suggest a weak shock but I think yours has a monoshock. It's not easy some times to inspect all those nooks & crannies around weld joints but It's also a safety issue when it's a suspension component. Just had a second thought. What shape is your front fork in?? It might be a Long Shot but worth a look if the fork tubes & sliders were badly worn on your fork legs couldn't that cause some yaw left or right?? Just trying to brain storm for you a little. Good luck Friend and Be Safe. It seems the Military from Nations considered Friendly to America are also under attack from Terror groups. Also Keep them Flying!

 

[billday]

Frederic,

Nice build! What fuel tank did you use?

Bill

 

[Fred]

Thanks everybody for brainstorming with me! Today in the afternoon I will recheck everything off the suspension.
@billday I used a Yamaha xs650 fuel tank. The tunnel was a perfect fit, the only thing i needed to adjust was the mounting point under the seat.

It's my first build and i knew it was a challenge because most of the time the DOHC are build with a bobber style.
But personally i prefer the café-racer style.
I'm glad with the end result, the only thing i want to change is the seat.
The current seat is self fabricated for 2 people, i made it because my wife can go ride with me.
But she recently bought a Honda cx500 so i don't need the duo seat anymore.

 

[Fred]

So a little update here on the engine pull.
i'm a little embarrassed to say that I forgot to tighten the bolt that was holding the swing arm.
When I was mounting everything I must have overlooked the bolt since I was very eager to try the bike.
But with that out of the way I can finally take the bike for a real spin on the road.
this weekend I mounted some extra silencers in the exhaust but i'm a little bit worried because it's still pretty loud.
Is it possible to fabricate an aluminum piece to put in the silencers or would that cause too much obstruction?

 

[Fred]

So here are a few pictures from the beginning too the end of the build.
First few are how i bought the bike.

 

[Fred]

the disassembly and cleaning

 

[Fred]

sandblasted some parts for the new paint.

 

[Fred]

Here i started with the new paint VHT engine paint.
I'm glad with the result.
after the paint i started the assembly of the motor, i changed the clutch plates and springs with new EBC stuff.
replaced piston rings, the chain, checked the valve clearence and alround new gaskets.
everything was checked like it was told in the manual.

 

[Fred]

 

[Fred]

The rest off the ^parts that my mate painted for me.
only the wheels and the swing arm are powdercoated.
The color of the fueltank and brake caliper is Ducati red.

 

[Fred]

 

[Fred]

 

[Myke Nytemare]

Wow... Very awesome! Great looking bike and work. I hope one day to completely rebuild my XS and get to paint/powder coat everything like you did.

Beautiful job.