KLR riders out there

[veny]

Whoohoo!
I better leave it on then

[warewolf]

I'd say it is the secondary air injection system. Under certain conditions as measured by intake vacuum (thin hose to carb) the valve dumps fresh air from A into the exhaust via B. That has two purposes: firstly to add oxygen to help complete combustion to reduce emissions, secondly to dilute the nasties with fresh air to reduce the emissions measurements (parts per million).

They are known to increase the exhaust popping on the overrun. Just got rid of mine on the 640A; it still pops but a lot less especially at lower engine speeds.

There is absolutely no performance gain to be had by removing it, except by removing weight: 440g for all the bits on the 640.

[pete376403]

Colin is correct, it draws air from up inside the frame tube and dumps it into the exhaust port. The US sites refer to removal of all this as "de-californication". MarkS bike had this removed - caused his retirement from the SouthCoast ride after the plug filling the hole in the ex port came loose - it made strange noises and had him worried.
The weight loss from its removal is hardly worth the effort.

You are better off spending the time looking for places where the electrical loom contacts the frame and rubs through the insulation. There's one spot just up from the valve in your picture.

[marks]

Colin is correct, it draws air from up inside the frame tube and dumps it into the exhaust port. The US sites refer to removal of all this as "de-californication". MarkS bike had this removed - caused his retirement from the SouthCoast ride after the plug filling the hole in the ex port came loose - it made strange noises and had him worried.
The weight loss from its removal is hardly worth the effort.

I think removing it lessens backfiring on decelleration

less crap on the bike is good - rip it off - just not while your bike is in warranty

[veny]

Thanks guys, spot on with the explanation(s).
I'll remove it at a later date.

Loom chaffing noted and I gave it a good going over, repositioning and cable tying where needed.
Also added an accessory socket

[Padmei]

Had a good shakedown ride around the forest today & with all the mods & new chain, sprocket etc it runs really smoothly. Whilst being hesitant doing the carb mods I have to say it has made a difference to the engines characteristics.
The increased bottom end power has made riding in 2nd gear over difficult terrain easier with no lugging (with a bit of help from the clutch) Sometimes I was riding in 3rd thinking I was in 2nd.
No bottoming out at all with the intimators.
Above all I am still so impressed with the 606 & E07 tyres today. The terrain was dry , loose & hard & the tyres excelled. Even when I stuffed up a line on a steep uphill a squirt of throttle had me hooking up with & blasting off the top.

Funnily as with a number of things, the harder I rode the bike, the stronger & more responsive it became.

[Woodman]

Had a good shakedown ride around the forest today & with all the mods & new chain, sprocket etc it runs really smoothly. Whilst being hesitant doing the carb mods I have to say it has made a difference to the engines characteristics.
The increased bottom end power has made riding in 2nd gear over difficult terrain easier with no lugging (with a bit of help from the clutch) Sometimes I was riding in 3rd thinking I was in 2nd.
No bottoming out at all with the intimators.
Above all I am still so impressed with the 606 & E07 tyres today. The terrain was dry , loose & hard & the tyres excelled. Even when I stuffed up a line on a steep uphill a squirt of throttle had me hooking up with & blasting off the top.

Funnily as with a number of things, the harder I rode the bike, the stronger & more responsive it became.

Ditto with the carb mods, no need to run a 14 tooth front any more really imho.

[NordieBoy]

Ditto with the carb mods, no need to run a 14 tooth front any more really imho.

Same with de-corking the DR.

Say 5% better de-corked.
A 14t is basically 7% lower.

Almost the same effect.

But de-corking + 14t is just more betterer.

[warewolf]

Ditto with the carb mods, no need to run a 14 tooth front any more really imho.

Geez I should pull finger and do mine.

[Howie]

Ok all you KLR riders out there, who has fitted after market HandGuards if so what brands have been used, and what were the pro's/ cons of your choice. IE ease of fitting, amount of protection to levers/ hands etc. I am looking at purchasing some soon.

cheers

Paul

[Woodman]

Ok all you KLR riders out there, who has fitted after market HandGuards if so what brands have been used, and what were the pro's/ cons of your choice. IE ease of fitting, amount of protection to levers/ hands etc. I am looking at purchasing some soon.

cheers

Paul

I got the maier ones from the states klr.com i think. very solid and strong and bolt pretty much straight on, and they are quite big so offer real good wind protectionn too, and were about the same price as comparable ascerbis ones at the time. came in klr red too. Happy

[Padmei]

I've got Acerbis rally pros cos they looked the coolest. To fit them was a bit fiddly - I had to spacer the ends so they'd clear the clutch & brake levers. I ended up cutting the knob off one of the levers to get them fitting right. I also had to grind off a thingy off the bar ( can't remember what it did) as it got in the way. I kept my barend weights on as well.

I don't think they offer that much in the way of wind protection however from the garks on them I guess they've saved a few swollen knuckles.

[Howie]

I got the maier ones from the states klr.com i think. very solid and strong and bolt pretty much straight on, and they are quite big so offer real good wind protectionn too, and were about the same price as comparable ascerbis ones at the time. came in klr red too. Happy

Thanks woodman, they look quite good, and your right the price is very competitive, with what I've seen over here, and they come in KLR black too.

I've got Acerbis rally pros cos they looked the coolest. To fit them was a bit fiddly - I had to spacer the ends so they'd clear the clutch & brake levers. I ended up cutting the knob off one of the levers to get them fitting right. I also had to grind off a thingy off the bar ( can't remember what it did) as it got in the way. I kept my barend weights on as well.

I don't think they offer that much in the way of wind protection however from the garks on them I guess they've saved a few swollen knuckles.

Thanks Padmei, I'm not that worried about wind protection, although it's nice on a cold winter's day. I don't have any bar end weights, as mine's the earlier model KLR.

[veny]

Had a good shakedown ride around the forest today & with all the mods & new chain, sprocket etc it runs really smoothly. Whilst being hesitant doing the carb mods I have to say it has made a difference to the engines characteristics.
The increased bottom end power has made riding in 2nd gear over difficult terrain easier with no lugging (with a bit of help from the clutch) Sometimes I was riding in 3rd thinking I was in 2nd.
No bottoming out at all with the intimators.
Above all I am still so impressed with the 606 & E07 tyres today. The terrain was dry , loose & hard & the tyres excelled. Even when I stuffed up a line on a steep uphill a squirt of throttle had me hooking up with & blasting off the top.

Funnily as with a number of things, the harder I rode the bike, the stronger & more responsive it became.

Can't do this yet..., but did you also drill the slider?
Instructions sure don't get any better than this.
http://www.klr650.net/forums/showthread.php?t=41112

Looks like it could even be done without completely removing the carb

[Padmei]

No I didn't drill the slider cos I lost the drill bit somewhere. Def don't remove the carb as they're suposed to be buggers to get back onto the rubber sleeves. My throttle securing screw was really locktited on I rooted the head getting it off - had to use vicegrips. Also be careful with the diaphram - a bit of grease holds it in place.