Blondie, XTZ660 rebuild

[mr_uks]

Thanks for letting me join the community, I hope to contribute with what I can.

Seems I have forgotten to introduce myself, sorry.
My fullname is Kostiantyn, "Kosty" is completely Ok )
I'm 33, from Zaporizhia, Ukraine.
Currently I own '96 Honda NX650 Dominator, also modified with WP front fork (cheaper old 4054, 40-mm USD from 1995 KTM LC4 620) and undergoing rear shock upgrade to WP, too. It would be interesting for me to compare this motorcycles when Tenere will be ready to run. I expect Tenere to be smoother and more capable of highway use, because it is heavier, have better wind protection, better fuel range, and from what I've heard and read, better performs at high revs, with less vibration and better top speed.
Well, we'll see, can't wait for it

[xtzrick]

Hi Kosty


Dynojet kits are designed for use with free flowing air filters (K&N etc.)
I'll check and let you know what settings my carbs have.
The #50 pilot jet will be a good choice

Rick

[mr_uks]

Hi Rick,
thank you for the tip regarding Dynojet.

To be honest, I have no particular faith in K&N or any other free-flow filter, because they require proper maintenance while their filtering ability is still arguable. In dusty regions (which I live in) or trail riding (which I love) I'd prefer to have a standard paper filter (which I have).
So, having that, should I switch back from Dynojet to stock settings, if I leave my (kinda-)Arapovic exhaust as it is?

[mr_uks]

ok, dynojet site provides this paper for XTZ660 stage 2 kit, and it says:

For mildly tuned machines using the stock air-box, with stock or K&N filter. May also be used with a good aftermarket exhaust system.
K&N Filter# YA-0080

http://www.dynojet.com/pdf/european/E4252.pdf

So, the stock air filter is applicable too, and I'd stick to that. But any information regarding carb settings will be a great help for me and much appreciated.


Disassembled the left carb today. Holy cow...

[mr_uks]

Finally, she's back to life (again).

The carbs were in a totally garbage condition, basically I have built a working set of carbs from a two pairs of them and a bunch of brand new piece$. Put a bigger (size 50) idle jet. Put an inline fuel filter, replaced the fuel lines and did a valves adjustment. And I should admit, what about the valves adjustment, this is the most uncomfortable bike for this procedure in my experience. After years owning NX650, which was so easy that it takes 40 minutes to do the valves job, i wasn't expecting that it could be such a pain. But I think I will get used to it.

Here she goes, looks like a bit rich from the idle, to be adjusted...

phpBB [video]

Still a lot of work to do, but at least she's breathing now. Can't wait to get her on the road.

[Red_Lion]

Finally, she's back to life (again).

The carbs were in a totally garbage condition, basically I have built a working set of carbs from a two pairs of them and a bunch of brand new piece$. Put a bigger (size 50) idle jet. Put an inline fuel filter, replaced the fuel lines and did a valves adjustment. And I should admit, what about the valves adjustment, this is the most uncomfortable bike for this procedure in my experience. After years owning NX650, which was so easy that it takes 40 minutes to do the valves job, i wasn't expecting that it could be such a pain. But I think I will get used to it.

Here she goes, looks like a bit rich from the idle, to be adjusted...

Bear in mind - there is a problem with the secondary carburettor axis is very popular in our post-USSR region (especially if it is often washed with a "carburettor cleaner" and/or reassembled with thick grease). This is combined not with the most successful axle design - the black antifriction coating wears off and begins to wash the axle from the body. It warps and the wear of the carburettor flap begins. Аxle seals stop working when the flap is opened or in general are defective - the air suction starts

From this, a lot of problems with the carburettor especially at idle speed - from the floating idle, to the need to twist the screw of the quality of the mixture of idling almost to the limit and the inability to fine tune the carburettor in general (with heavy wear).

If you look for another carburetor, then pay attention to the secondary carburetor's flap from below on the thrust side - there the "step" around the axle is milled. The more step - the worse.

This can all be repaired, but more expensive depending on wear and tear - from updating the antifriction coating, sealing flap and replace seals, to the need for a new axle, flap and bushings (in case axle 9mm).

[mr_uks]

To be precise, I think it's primary carb you are talking about, not secondary.
Both carbs were rebuilt, the throttle shaft seals also were replaced with the brand new Yamaha OEM parts.
I don't like USSR approach of doing things )

[Red_Lion]

To be precise, I think it's primary carb you are talking about, not secondary.
Both carbs were rebuilt, the throttle shaft seals also were replaced with the brand new Yamaha OEM parts.
I don't like USSR approach of doing things )

I talking about secondary (cv-type larger carb on right side). For him you can't buy OEM seals - no part number. Also, based on the service manual and the spare parts catalog, Yamaha considers the axle, flap and seal not requied disassemble and changing only with body.

For you also some pictures from internet:

Axles with wear (top - 1.2mm wear on 8mm axle):

And how flap close with this axle:


Here you can see the traces of air sucking through a closed flap (anover carb, wear just started, but seals probably dead):

[mr_uks]

Oh, that's epic.
Thanks for the info!

[hannesf]

Hey, this is an incredibly useful thread!!! Thank you for alle the informations!
I am also trying to figure out a good jetting for my carb on a 3YF with a staintune exhaust.
what would be the first jets i would have to replace? With the Exhaust i also already ordered a K&N air-filter...

What would be a good start for the jets?

Cheers and thanks!!!