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Akrapovic Exhaust : Loose bolt & Rejetting advice

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Hi guys,

 

 

Just picked up a 2010 DRZ 400s with 5000km's on it , and a full Akrapovic Ti Exhaust.  Foam air filter.  Otherwise stock.

 

I have some questions on jetting, and header bolting.

 

1:  noticed the exhaust header was loose, and that the left header bolt isnt screwed in all the way....and doesnt seem to want to screw in any further.  This means that I've got an exhaust leak, the bike has been running lean, and that it started to melt into the coolant hose!  Bolt doesn't look stripped, and I doubt the exhaust is supposed to fit loose....   Anyone experience similar problems?  I shouldn't have to ream the bolt to tighten it..... IMG_20140209_115456685.jpg

 

but it doesn't want to go any tighter, and theres a pretty big gap.

 

2: Jetting

 

 

The bike is running on stock jets.  I'm guessing with the exhaust flowing more, I should be runnning different jets.   I also may do that 3x3 mod......  but if I do/don't, how do I know what jets to switch in?

 

 

Noob to working on thumpers.

 

 

 

Thanks for any advice in advance!

 

 

 

POOT

Edited by POOT

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Ok , this is what I would do , considering that the bike is new to you , Remove the exhaust system . check that there is a gasket situated in the exhaust manifold . They are hard to see so have a real good look . You now have the option of fitting a new gasket too .

Removing the exhaust will give you the opportunity to inspect the threads and the bolt , use some lube on the bolt when you fit the pipe .

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Sounds like the previous owner didn't install the gasket.  Pull it off and look, if not get one from the dealer.  If the header bolt is still bottoming take it out & grind it down until it tightens properly. 

 

As for the jetting.....Without 3x3 get a Dyno Jet Kit.

 

If you do the 3x3 get a JD Jet Kit, both kits come with jetting instructions.

 

 

Welcome to TT, it's addicting !

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Firstly decide if you want to upgrade to an fcr or stay with stock paperweight.....

DRZ400S/SM FCR-MX 39mm Conversion Kit

 

For stock carb,open pipe and 3x3 mod (@near sea level)

Buy a JD Jetting Jet Kit - DR-Z400S/SM and a ThumperTalk DRZ400S/SM Extended Fuel Mixture Screw

160 main jet

Blue needle clip 4

22.5 with extended fuel screw or 25 pilot jet with stock fuel screw

2.75 turns

 

 

 

Edited by Craigo 485sm

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OK. I will take the exhaust off. The right bolt screws in properly...so Would it still be a gasket issue ?

I think I'll stick to stock carbs because I'm just keeping the bike for a few months while I'm living here in Tasmania.

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OK. I will take the exhaust off. The right bolt screws in properly...so Would it still be a gasket issue ?

I think I'll stick to stock carbs because I'm just keeping the bike for a few months while I'm living here in Tasmania.

You won't really know until you take it off and look.  Perhaps pick around in there with a screwdriver (without gouging).

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I think I'll stick to stock carbs because I'm just keeping the bike for a few months while I'm living here in Tasmania.

 

Ok, so you don't want to spend much coin on it?....If it's not surging or has a high rpm misfire just ride it ....

If surging the low cost option is to fit the stock exhaust ....or put a spark arrestor in the akropovic,....or keep the akro as is, fit a thin washer under the stock needle and use a larger main jet

The last option is pretty bodgey and you didn't hear it from me...ok...LOL....

Edited by Craigo 485sm

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I ended up getting the JD kit and will do the 3x3 mod. Also going to get the exhaust gasket and hopefully its an easy fix.

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I ended up getting the JD kit and will do the 3x3 mod. Also going to get the exhaust gasket and hopefully its an easy fix.

 

Good....There is a Youtube vid that may be helpful with the install procedure...

 

160 main jet

Blue needle clip 4 

stock 22.5 pilot jet with ThumperTalk DRZ400S/SM Extended Fuel Mixture Screw or 25 pilot jet with stock fuel screw

2.75 turns

 

 

 

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Good....There is a Youtube vid that may be helpful with the install procedure...

 

160 main jet

Blue needle clip 4 

stock 22.5 pilot jet with ThumperTalk DRZ400S/SM Extended Fuel Mixture Screw or 25 pilot jet with stock fuel screw

2.75 turns

 

 

 

 

 

Important question:   Should I have ordered other jets along with the JD jet kit?   For some reason I assumed it came with everything.. ....

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Important question:   Should I have ordered other jets along with the JD jet kit?   For some reason I assumed it came with everything.. ....

 

No it has all you need, .......The only item you need to order separately is an extended fuel screw

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So I just took off the pipe, and the exhaust gasket was in there.....

Is there any chance the akrapovic exhaust is supposed to go in without the exhaust gasket? Not sure why else there would be that big space and there's definitely an exhaust leak because of it

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I guess that space is just due to the flange.... I reinstalled the system and its still there, but I tightened it so that the headers no longer resting on the coolant line.

Tomorrow: replace melted coolant line and put in fresh juice

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It should probably be mentioned that the flange should not be touching the head. You should have a gap between that flange and the head. If you did get it to tighten down all the way, it would be way over tightened. Those bolts don't need to be super tight, in fact it's possible to create a leak like that. Ideally you want to torque them to 16.5 ft-lbs. You also want to tighten both sides down evenly as possible (so don't tighten one side then do the other, take both bolts down evenly).

 

Anytime you have different metals (steel bolt / aluminum head) anti-seize should be used. Especially since anti-seize will hold up to exhaust temperatures.

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Thanks for the tips. I don't have any anti seize and I have to take it to work now....but I figure I tightened them up evenly..... And did them tight to the point where the header no longer moves around like it did. I only had an Allen key so i don't think I over tightened it.

I suppose I will have to wait until I get the new jets in with the 3x3 mod to see how she's running.

How would I know then if there's still an exhaust leak?

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Well.... Just rode to work. Things seemed better with less backfire, but when I got here the header was back on the coolaNt hose! The header still moves even though it was firm last night.

What gives???

1393445814269.jpg

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Something odd is going on for sure...So you seem to think the distance between the flange and where the gasket meets the header is too short.???

It's hard to tell exactly the situation without seeing, is it possible to take some pics of the flange area when the pipe is bolted up securely ....??

What is the origin of the pipe ?..Is it made for a DRZ or was it modified to fit from another bike??

Edited by Craigo 485sm

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Something odd is going on for sure...So you seem to think the distance between the flange and where the gasket meets the header is too short.???

It's hard to tell exactly the situation without seeing, is it possible to take some pics of the flange area when the pipe is bolted up securely ....??

What is the origin of the pipe ?..Is it made for a DRZ or was it modified to fit from another bike??

 

 

I've got a pic in my first post, but i will snap some more tomorrow morning.

It seems like there  is supposed to be a bit of space between the flange and the studs, which I was at first worried about, but my problem now is that even though I tightened down on the bolts,  tand put in a new exhaust gasket, the header pipe ends up resting on the coolant line.  If I grab it, I can move the header pipe up and down by about 1/3 of an inch in front.  when I had it off, and reinstalled it, it seemed tight and was not resting on it, but after a ride, it went back to resting on it.

 

I just bought the bike used two weeks ago,and it came with it on, but it should be the full akrapovic Ti system for the DRz.  400

 

I'm perhaps a little unevenly tightened on them, so I'll try loosening the bolts and doing it a little more evenly, but I figure if I do it looser, its just going to rest on the coolant hose for sure.

 

 

Stumped.

Here is a similar question regarding the spacing, but no one mentions any problems with the pipe resting on the coolant hose.

 

 

http://www.thumpertalk.com/topic/288459-akrapovic-ti-installation-questions/

 

 

Cheers

 

 

POOT

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