FZR RRSP 3TJ7

[willandrip]

"So the 0.2 difference is nothing to worry about then?"

You would not even see it with an analog meter !

Digital meters are great in some respects but also tend to lead owners down garden paths to chase wild geese off the lettuces.

"Keep the fuel levels high if the plugs are dry" is going to be my new signature.

What are you gonna do about them coils/leads. ?

[Drunkn Munky]

Thats pretty much what the seller said about the coils so i guess there ok, leads are going back to be replaced though. Trying to get the fuel level between 20.9 and 21.9mm was frustrating to say the least but there all around 20mm give or take now.
Unfortunately ive ran out of time with this bike (baby due in a week or 2) so it'll go back into to storage until i get time to work on it or someone buys it.

[RSVR]

Tony,

More babies......! bloody hell.

One's enough for me.

Best of luck matey

[Maelstrom]

All the bikes that I have checked with BDST carbs show the fuel level as being similar to the TDM850. That is in about halfway between the line that is in the middle and the "Mikuni" line.





The information that is in the SP manual is weird.

Here are some models of my BDST carbs from my FZR400 3TJ1.
The first one is vertical.
next is with the carb tilted at 15 degrees from vertical and the other is at 20 degrees.
The distance is measured vertically from a horizontal line through the centre of the needle jet to a horizontal line drawn through the "float chamber line" on the float bowl.
At 0 degrees (vertical) the centre of the needle jet is 11.0 mm above the line.
At 15 degrees the centre of the needle jet is 20.1mm above the line.
At 20 degrees the centre of the needle jet is 22.8mm above the line.
At 21mm below the "Float Chamber Line", which is what the manual says, the float bowls will be empty.






cheers
Blair

[Maelstrom]

And here is another one. The YZF750 which also uses BDST carbs.


My guess on the different values is that the carbs on each model may be at slightly different angles.

[willandrip]

This is why fuel levels are best done by the book with the bike upright and the wheels at the same height;
not the rear jacked up on a stand.

It was discussed in another post previously.

Float heights never seem to translate to fuel levels accurately but many seem to have better results by
doing it that way and on the bench to boot ! I could not fathom how they got the angle the same as when
fitted to the bike even after enquiring.

Float levels also require the float needle springs to be all of the same tension.
There is a very recent thread here if one cares to look.
http://www.exup1000.co.uk/phpBB2/viewtopic.php?t=13044
showing how a saggy needle spring would effect heights and make float height setting inconsistent.

The TDM 850 3VD and the FZR1000r effectively share the same carb, along with the Ducati Superlite .
The difference is in the float bowls which do take into account the mounting angle.

[Maelstrom]

Maybe I am clear as mud. Wouldn't be the first time.
The only reference that I can find for 3TJ1 fuel level is in a manual that is listed for the
3TJ1 and SP


This diagram states "20.9 to 21.9mm below the float chamber line"

I am assuming that the diagram is showing the fuel as per this coloured image.

This diagram makes no sense at all to me. The float bowl is virtually empty. The fuel level on every other BDST carb, some of which I have previously posted, places the fuel level about 10mm above the centre line. Or like the TDM850 it is approx 15mm below the Mikuni line. This means that the fuel level for the 3TJ1 is approximately 31mm lower than every other BDST carb used by every other bike.


If someone can explain this diagram to me then that would be good.
cheers and thanks
Blair

[willandrip]

Blair; I have hunted about for another manual also;
All sites that have one, show a copy of the same scan as yours .
The quality leaves a bit to be desired and the important bit (that shows the datum line from where the measurement
is to be taken; the next page to the one you have shown) is nearly totally obscured.

The drawing you have enclosed from the manual just seems to be a generic one used in a lot of manuals.

Could it be the datum line is; as the TDM; using the underside of MIKUNI,

That would look to bring the level to be between the center line and the MIKUNI line.( somewhere near what is usual)

Setting as per the manual cannot be right ;as you state; no fuel in the bowls.


Pic; courtesy of Chris.

[Maelstrom]

Yes, I thought about that possibility too. It is either that or everything is wrong including the 20mm value.

Unless we can get hold of some more information from a Yamaha document, I think the best course of action would be to create a consensus of what owners find when they check their fuel levels; hopefully with float needles in good condition. Then if we can get some input make it a sticky and I will also make a page on my web site.

[dobbslc]

If I can pull out of the treacle of apathy I'll level my bike off and see if I can get a measurement with a clear tube.
It runs and starts well so should give you an idea of what to set the carbs.