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08 FE650 Performance Upgrades

Joined Jan 2014
186 Posts | 99+
Central Point, Oregon
Looking for info on performance and reliability upgrades for the FE650.

I am currently running an Akrapovic muffler. How do I tell if the head pipe is Akrapovic as well?

Anybody used these guys performance parts?

Use the arrow slide inside the central box to see all the trick parts.

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Hi

I use a 105mm "kit" from JBS, the piston/liner are very good http://husaberg.org/mechanical/11677-jbs-700-kit-welded-80mm-crank.htmlproblem now is getting in touch with them seems to be near impossible for the last couple of years.the liner is made by westwood in the UK and the piston is a custom CP

DCR racing in the UK also do a kit with the alloy liner with an RC8 piston i think about 103.6mm but i never read anything about it other than its availability

travis at thumperacing in the us has done some bergs id ask him if he can do an oversize iron liner/ piston and get it together to match one of his stage 5 cams with oversize KW valves.

but the stock cam is very good, good peak power and good peak torque just a little lumpy in delivery, other available grinds smooth things out but loose either torque or power unless you up the cr. there is a Wossner ktm 540 piston that will fit that reduces the head volume by 10.5cc... cr should be about about 13.75:1 , haven't tried it. wossner 8583D. there are also aftermarket pistons that are copies of the OEM, by pro-x and wossner. prox is the cheapest ill get the part number lateron.

the akro headers try to be the same length, the oem ones are different lengths.

the stock 08 engine is really really good and the most reliable of all the older bikes. take off teh ignition cover and check the crank endfloat is at least 0.5mm and if inside use NTN roller mains instead of SKFs, http://husaberg.org/mechanical/17170-definative-main-bearing-thread.html

porting and oversize valves smooth it out a bit, can use anything designed to fit in the KTM rfs heads .. KW oversize valves, ktm rfs cams fit if you cut the waterpump shaft off. can use sintered iron valve guides from a KTM 450, I got mine from Dave hopkins (DJH) on ktmtalk.

sometimes the single valvesprings break , KTM dual valve springs are the cheapest, kibblewhites are the best http://husaberg.org/mechanical/10680-all-about-valve-springs-nice-pics.html some people have the cam follower bearings go at 2-300hrs others get 500 hours out of them, the ktm part number is 590 36 061 090

gearbox circlips are a weakpoint, use kawasaki part no 92033-1089 instead, 5pcs

FWIW When I put the akro silencer on the stock engine it lost bottom end but the bigger bore loves it.

stock jetting is a bit lame but you should have the EKR needle as stock which is a pretty good needle, best thing I found is to set the main air jet at roughly the same size or slightly bigger than the main jet, the rest is just fiddling till you are happy.

carbkie.html, Keihin FCR Carb Tuning Procedures

edit; can bore the carb to 43.5mm as well, there are billet carb centre pieces available for this from Thumperaccing in the US

Have fun
cheers
Bushie
 
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I am currently running an Akrapovic muffler. How do I tell if the head pipe is Akrapovic as well?

I believe the connection btween the Akrapovic headers and midpipe has the retaining springs on the outside, standard pipes they are on the inside.

The Acrapovic has a smooth and gradual union from two into one.
The standard is somewhat pinched at the Y, and goes from two into one in a short distance.
 
the pro-x piston number for the 08 628 ("650") is 01.6606 there is another one for the 82mm stroke 644

oem headers different lengths

images


akro trying to make both headers the same

images


as idle points out also a nicer 2 into 1 and i think the mid section of the akro is sometimes in 2 pieces
 
Hi,

I am finally at a place (I hope) to buy some cool parts for the fe650. I am wanting to buy the lighter fc flywheel, Akrapovic header pipe, and hopefully a steering damper.

Couple questions and thoughts:

I was reading here- I Love Akrapovic that this guy had his 650 dyno'd with full system and ended up doing some jetting work to gain 6 horsepower and 3nm of TQ!!! Anyone know these jetting specs?

I can not find this header pipe on line in the USA any help????

Stoked about the lighter flywheel for quicker rev and quicker turning!

Anyone recommend a steering damper for this bike???

Also, looking at some WARP 9 sm wheels for $200!
 
Underbar Scotts/BRP damper kit on my 07 FE650:

DSCI0555%2520%2528Medium%2529.JPG




Before, during and after jetting of my 07:

650Dyno.jpg


Note that FWIW the Dyno Dynamics 43 Hp supposedly equates to 63 Dynojet Hp. Whatever the numbers are, its bloody fast. Apparently ported CR500s make 39 Hp on this dyno.

The setup includes an opened up stock muffler and a Lineaweaver needle.
 
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if you go akra try and get the full system

I put the akra slipon on my 08 and it lost bottom end compared to my stock muffler with straight through endcap, Simon found the same.

the 700 loves the akra

some good gains to be had from tidying up the 2 into one join on the OEM mid pipe and grinding out the welds inside the headers.

I ran a scotts damper on the stock frame, new frame doesn't need one
 
Thanks for all the info!

Since I have the Akro slip-on I wanted to finish the system in stainless. A part number would be handy since I am lost trying to find this header pipe.

These must be numbers from a Dyno-Jet.

08 FS650E

57.27hp before 63.07hp after Akro full system
42.08nm before 45.48 after Akro full system

Thoughts.......
 
my 400 gave 46rwbhp 10 years ago and it wasn't even fully tuned and I was on knobblies!

that's poor.

Taffy
 
my 400 gave 46rwbhp 10 years ago and it wasn't even fully tuned and I was on knobblies!

that's poor.

Taffy

But all dynos are different. They are a tool, and what's important, is what achieved when using it, the before and after. The absolute numbers are good at the Pub, and that's about all.
 
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steve

trust me, they are poor numbers.

I did a a KTM LC4 last week, customer had had it 3 years and was P****d off with it as it would never start and run nice byut was "ok" after idle.

the cam timing was two teeth out. I gave him his bike back and he says he has had to have his bum hole sewn up...

I won championships with my 400 Steve, it was good 'under the graph' - it HAD to be. mate it isn't personal, I'm trying to tell you it isn't right.

having someone "thank" you for your reply is like being given a band aid after you took a bullet.

regards

Taffy
 
Sorry Taffy, there is absolutely nothing wrong with my FE650, its a missile as is.

One of my ongoing pleasures in life is seeing peoples facial expressions after a test ride, then hearing their verbal feedback. Makes modern 450s feel like doughy 250s.

Like I said, its not about the actual numbers on the dyno, its about the before and after achieved by the tuner. Same dyno, ported and piped CR500s setup for dirt track, get 39 Hp. That's the comparison that's relevant :eek:
 
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FWIW that particular Dyno is known as the "heart breaker" and for good reason

typically people get 12 to 15% higher results on other dynos

hey look I just gave you bandaid for your bum hole taff ol son LOL
 
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