XT's 2nd carb?

**Kennichi** · #1 23rd April 2009

Hi

At what point of the throttle being opened does the 2nd carb kick in? , in that C Scott's book again states I should be able to feel it kick in , I'm still not that used to big singles and I twist the throttle and it gets louder and goes faster.

As stock at what point does the 2nd carb kick in 50%? , 75%? ,

Turkey with its $$$$ petrol will mean I want to stay on one carb for the easy bits to save fuel ~ £2 a litre of petrol I want to go easy on it and get at least 14~15 miles per litre and maybe more as some people on the Hubb claim 20~23 miles per litre. Though with the extra load I doubt this is possible.

However old habits die hard in that on my CBR I ride in 6th even at 30mph and the bike is fine...

Any thoughts?

Thanks.

**bruken** · #2 24th April 2009

Which XT do you have? There are variations. As an average tho on 600's after 6mm on the CD the second carb should begin to actuate, which roughly equates to cruising at 3.5krpm +- 50mph before the second carb opens. I seem to remember the 550 being 10mm, but couldn't tell you about any model after 1990.

**Tenere Tom** · #3 24th April 2009

If you take off the inlet rubber on the right hand side of your bike you will be able to see the 2nd carb in action.

I did this just to make sure mine was operating as it should be (and it was).

I still think mine has issues when the engine is warm (it's fine when it's cold).

**Kennichi** · #4 25th April 2009

Right thanks I'll have a look under the rubbers, bike is an XT600E , problem is with my XT600E is that its the really bare bones version it has no technometer so I can't tell really use the revs to guage anything and I've not bothered looking up retrofitting one either , more cost and probably more to go wrong!.

***Touring Ted*** · #5 25th April 2009

I had a 2003 XT600E

I couldnt feel the second carb kicking in. It felt seemless. !!

**BlackDogZulu** · #6 25th April 2009

I have a 1995 600e, and I can't feel the second carb kicking in either. I'm sure that is as it should be. As to the absence of tachometer - do you really need one? Mine has a much more basic engine revolution meter, which runs:

* hands tingle
* feet tingle
* arse tingles
* tooth fillings loosen
* vision blurs
* little red 'Rev' light comes on.

It works for me.

**bruken** · #7 26th April 2009

Quote:

Originally Posted by BlackDogZulu

I have a 1995 600e, and I can't feel the second carb kicking in either. I'm sure that is as it should be. As to the absence of tachometer - do you really need one? Mine has a much more basic engine revolution meter, which runs:

* hands tingle
* feet tingle
* arse tingles
* tooth fillings loosen
* vision blurs
* little red 'Rev' light comes on.

It works for me.

On my 3AJ i dont feel the second carb it comes in too early imo. On the XT550 ...yeah you felt it, doubly so because it came in sweetly on the torque curve. It was like the powerband on a 2 stroke. Real sweet. Only problem with that set up though was the mid range lagged a bit. But I can remember doing sixty mph in 5th, dropping to 4th and winding open the throttle, she'd fairly skip. Memory is a funny thing though. 25 years ago that kind of power was extraordinary on a thumper. Nowadays it'll probably feel like you're riding a lemon. Excuse me while I fetch me pipe and slippers.

**Kennichi** · #8 26th April 2009

Quote:

Originally Posted by BlackDogZulu

I have a 1995 600e, and I can't feel the second carb kicking in either. I'm sure that is as it should be. As to the absence of tachometer - do you really need one? Mine has a much more basic engine revolution meter, which runs:

* hands tingle
* feet tingle
* arse tingles
* tooth fillings loosen
* vision blurs
* little red 'Rev' light comes on.

It works for me.

Sounds like a plan.....

I've always been sceptical of the little red / rev light in that because it comes on when the ignition is turned on but the bike not started I assumed it was a mislabled engine oil pressure light.

**Kennichi** · #9 26th April 2009

Quote:

Originally Posted by bruken

On my 3AJ i dont feel the second carb it comes in too early imo. On the XT550 ...yeah you felt it, doubly so because it came in sweetly on the torque curve. It was like the powerband on a 2 stroke. Real sweet. Only problem with that set up though was the mid range lagged a bit. But I can remember doing sixty mph in 5th, dropping to 4th and winding open the throttle, she'd fairly skip. Memory is a funny thing though. 25 years ago that kind of power was extraordinary on a thumper. Nowadays it'll probably feel like you're riding a lemon. Excuse me while I fetch me pipe and slippers.

Surely the 3AJ had a tachometer? , swap you me heavily upgraded XT600E for yer 3AJ! oh wait the 3AJ doesn't come with a kicker....

**Jens Eskildsen** · #10 26th April 2009

I have a 2003 xt600e and cant feal the 2nd carb kicking in either. The whole powerband just seems smooth.

**BlackDogZulu** · #11 26th April 2009

Quote:

Originally Posted by Kennichi

Sounds like a plan.....

I've always been sceptical of the little red / rev light in that because it comes on when the ignition is turned on but the bike not started I assumed it was a mislabled engine oil pressure light.

According to the manual, it is called the "REV Indicator Light". On non-tacho bikes, it comes on as an IGN light at first, and when the bike is running it acts as a over-rev warning, coming on at 7k revs, I believe. I've only seen it on once. Never again. Not only my fillings - my teeth were falling out.

**Kennichi** · #12 26th April 2009

Quote:

Originally Posted by BlackDogZulu

According to the manual, it is called the "REV Indicator Light". On non-tacho bikes, it comes on as an IGN light at first, and when the bike is running it acts as a over-rev warning, coming on at 7k revs, I believe. I've only seen it on once. Never again. Not only my fillings - my teeth were falling out.

I've not felt that bad yet and mine was down geared, seems like a good bike to use as transport for dates then I suppose

**BlackDogZulu** · #13 26th April 2009

I suppose if a ride on the pillion has the effect of loosening their knicker elastic, then yes!

**bruken** · #14 26th April 2009

Quote:

Originally Posted by Kennichi

Surely the 3AJ had a tachometer? , swap you me heavily upgraded XT600E for yer 3AJ! oh wait the 3AJ doesn't come with a kicker....

You're quite right sir, so in return my 3AJ has been heavily upgraded with XT600E kickstarter parts.