FE501e 2001-2003 Performance Jetting Kit

Hi

I have been working on a performance jetting kit for my bike which is a well set up FE501e 2003. It has my jap rod in it for testing and until now just the 'easystart kit' for ease of starting.

recently i changed a lot on the carb and the PJ was forced up into the 50s! and the bike absolutely flew! it turns out that these bikes are screaming for huge PJs, but only if you make 4 changes to PJ, slide, atomiser and needle.

by changing the atomiser, slide, choke, PJ twenty times etc etc I now have a weapon! there isn't much 'snorting' through the carb now either, the engine is creamy rather than harsh and it devours revs.

the kit is £108 in the EU and 90gbp outside. I'm looking for owners now to test the kit on their bikes. so i know that the state of engine, poor fuel in the USA, altitude, ignition timing and most of all; 'valve clearances.....' will all play a part! it'll be enough getting these things right.

starting is first time all the time. that is now a 'given'.

so sticking with 501s 2001-2003 will be enough.

after this, nobody will pay $500 for Keihin FCR again. the difference at low revs where all the dirt boys play is huge. I say 'huge'. that is a big statement....

there will be instructions and i'll work 1 to 1 work with the first owners trying this so please contact me and let's get these dell orto's rolling!

Steyel? where are you!

regards

Taffy

2 days, 2 sets going out.

yippee!!

taffy

anybody else with one of the 2001-2003 501s?

looking to spread the news and get some feedback here.

regards

Taffy

2003 501fe carb kit

Hey taffy I would love to try one of these kits. I have a 2003 501fe with an Inop electric starter but plan on getting the gear assembly from you soon. However being here in AZ,USA at 5500 ft my berg is a pain in the foot(***) to start when hot most the time I can't get it started. Let me know what is needed from me so I can get one of the easy start kits. Thank you

hey there....do we have any kind of name?

it is for sale in my webshop as 101222 or just put 'berg booster'. I have about 8 kits out now but no reports on it. Just one Englishman that said this week he can't set it up in an email. I will be working with him I hope so we have a happy clappy camper.

I write at this time, on the Easter saturday, the hope is to start testing again of a home modified needle and if all goes well, I will have it manufactured. but that is months away.

right now, I need others to have good results with it and prove that a (not so) competent Jetting Guru can get it to work. email me if you don't want to go through the shop.

make sure that your tappets are good, your air filter is clean and not over oiled, use an iridium plug, and after that we can say you've done your best!

Taffy

Hi Taffy,

I have a 2003 FE501E as well and I love it. Have had it about 6 years. Proper pig to start. Have to kick 6 or 7 prime kicks then it will fire for a bit. Same process about 4 times and she will run. Dellorto carb has quite a bit of wear between slide and barrel wall, so my assumption is that it is knackered. barrel wall is scored/scuffed.

Am just getting back to riding it and at 52 don't have the patience or strength to kick the bloody thing. E Start system works fine however will not start the bike.

Valves and cam are new and set to 0.10mm.

Would love to know where to get another Dellorto from as I would like to keep it as standard as possible. Bit of a purist....

Appreciate some help please as it seems that you have yours firing well.

Thanks heaps.
Nathan Crosby

I just got 3 new brass slides. last ones left!

100390 in my web shop. £80.75 is about $105. but post is cheap at £8 so that makes up for it a bit.

look at the eeasy start kit if you want help starting it and my special choke cable.

Taffy

Having continued work on the jetting until last April, I finally stopped having altered that tiny air jet on the left as you look at the front face of the carb.

that was the last thing I did at the time. by lowering that jet I was able to reduce the air going in and pulling on the pilot jet (PJ) and numbers came down fast.

anyway, this could only be done with some kind of incremental jetting system so the old brass ring was removed and a pair of holes drilled and threaded for both the Pilot Air circuit and the Main Air Circuit. So with the help of my engineer, I had regular Dell orto 5mm PJs turned down a little and they fit JUST inside the O ring running round the underside of the Air Filter Adapter (AFA).

I think I could have used a better jetting system and stolen some small jets from Keihin or Mikuni. The hole is 4.0-4.2mm and both the above make 4mm jets. I'll see if there isn't enough contact are to thread them in.

So with the smaller PAJ I was able to reduce the PJ and the slide cutaway height which meant I could reduce the PJ some more and in the end the numbers were very low and still the bike ran well.

THERE ARE OVER 20 KITS OUT THERE NOW WITH FE501e OWNERS. all I hope enjoying the ride!

anyway, about 2 Months ago, under lockdown I kept thinking about a nagging little vibration at 2mm of throttle that I have never been able to get rid of. whether the 58PJ was fitted or the 38PJ, those of you running a roundslide Dell Orto will know it; a small mmmmmmmm drrrr mmmmmmmmm.

So, I started to think of how I might get rid of it and started testing again only last week. I was forced into changing away from the DR atomiser at the same time as I tried a new atomiser bush. I'll let you know when it is complete but it has been brilliant!



Please note; in the second photo a Dell orto mistake. they supply Fuel Valves with various fibre washers. there is no telling what they will put in a kit but unfortunately they are usually 1mm thick fibre washers and should be around 0.6mm. They do make 0.6mm and sometimes I'll even get a FV with them in but nobody knows what they will get. Notice the Brass arm is a long way from the correct angle. This will ruin your jetting on its own.

Taffy

Having last week changed the atomiser bush I thought I'd share with you what it is. photo 1.

this has created a windbreaker and with an AB/AR atomiser I have a bike that won't stall.

this was one helluva leap but was worth it. after 3 nights of testing last week I was back to level with the old DR atomiser system.

If you look, the thread for the AR and AB atomisers (see the second photo) is BELOW the hole through the angled atomiser bush. this means that air comes in the front face of the carb through the 6 0' clock hole (see the right hand hole in my previous post here) and goes through the bush hole and up the outside of the flue on the AB/AR atomiser. this is exactly what the MAJ hole was designed for. for the air to enter and go UPWARDS and it bleeds off the MJ from maximum power to the redline helping create power between the max. power and the redline. the longer and better it does this the better the 'overrev' is.

sadly, with the DR atomiser the air enters through the original flat-topped atomiser bush hole, the threaded area is ABOVE the port hole so the air goes DOWN and airates through the tiny holes in the DR atomiser (DR is on left - note the highest tiny holes).

the fuel sits above all the little drilled holes but momentarily goes down as the throttle is opened air then gets sucked through the tiny bleed holes leaning the mixture off.

a second disadvantage of the DR atomiser is that when air goes across a level hole there is a vacuum formed over the hole to suck up fuel but there's also an increase in pressure on the trailing edge stopping the fuel leaving the atomiser.

imagine a ping-pong ball in the atomiser. as it gets sucked to the top - it can't actually leave?

there are many ways of protecting the bush but the windbreaker system is the best and look how Keihin do it..... The AR/AB atomiser exit is flat on the bottom (just like the Keihin shown) and so is the DR but, it has a shroud above and it has, as mentioned above, no air wrecking the pick up in the base area.

so I now have a knock out steady idle.

Next report is of the work on the needle...............

cheers

Taffy

Attached are two photos. one is of the standard route that air takes around past the choke jet.

Dell orto supply choke jets from #40 all the way up to #155. It is difficult to imagine a #155 but the size of that bypass hole tells you that it was made for any such jet and not for the lower end.

All 'Easystart' and 'Bergbooster' kits use the smallest choke jet; the #40 which is one size down from that supplied to all round slide PHMs circa 2001-2003.

I have been experimenting with a faster air speed through a smaller hole but with no real effect.

back in 2002 when I first got my bike; an FE400e, I did some jet testing but proved rubbish at it, I made little progress and life also got in the way. the problem was, you had to draw every needle yourself.

I did however, for one day, get a screaming choke start!!!!! this is what I'd like again.

has anyone any knowledge of what makes Jap bikes rev so hard when starting?

regards

Taffy

I thought I'd show a couple of interesting mods that (typically) Husaberg never did to their bikes but others have.

the photo through the carb is of a Husky PHM carb but they used the alloy slide and you can see the ditch in the front face for the accelerator pump to operate.

so look carefully at the back to the left of the needle, a Husky cut out a notch. this forces the air mostly under the middle of the slide and then around the atomiser WHICH IT HUGS and then leaves via the middle. this means valuable fuel fuel is being sucked, lifted and carried out by air that never strays far off the middle path.

The second photo is one of three I have marked "strauss" so i trust he was an Austrian composer that had a Husaberg in 1784.....

In his photo, he's doing the opposite and spreading the air out "away" from the middle. those cutaways look quite tall but think about it; the venturi is ROUND and therefore the curve 'upwards' of the venturi means this will only appear as a tiny curved slit. like a 70s 'smiley'!

My money is on Husky having it right.

it would be interesting to compare the 'round' atomiser bush versus the 'bishops mitre'.

Taffy

Whilst developing the perfect needle I have had cause to thicken the tip or 'root' of the needle. i dipped it twice in a pot of laquer and then cooked it for an hour before turning smooth and round in the drill with P600.

once it proves itself to work - even once, it goes into the next redesign.

Taffy

Well that thickened tip wasn't needed in the end.....

Those who have had the bergbooster kits will know that the needle chosen needed to be in clip SEVEN, yup SEVEN!

I have been having three additional clip grooves added but everything has to start somewhere! when I was out testing one day it dawned on me that I needed the needle lifted higher than clip 4 so I looked around for anything on the;
bike I could use - nothing!
myself - nothing!
among my sparten tools and rucksack....not a sausage!

so all i could do in the end was 'eat the box that feeds you'!

regards

Taffy

thought I'd pass on some more handy tips for when working on a dell orto carb - especially on the 501 or 550. note the photos below and an amazing little spanner that American customer sent me F.O.C years ago as a thank you. (it wasn't bushie....)

with this spanner and a 1/4" drive 3mm allen screw I can get the Air Filter Adapter (AFA) off to do the air jets and also get at the pilot and choke jets.

indeed if I had a "fat" flat-bladed sscrewdriver end it would do the MJ as well.

an amazing friend!

when removing the floatbowl on the 501/550 you do the opposite of logic, you push the base ever-so-slightly away and the FB clears the choke jet....sweet!

Taffy

while working with the K series needle i discovered one serious floor in the design. so each needle I work on now has to have material removed.

I tried the drill in the drill stand and upright but you have no control and can see nothing. so the drill is now in the vice.

I mark the area I want to rework by scratching a deep line top and bottom. as I rub it down, the sharp (not very aerodynamic) edges come off.

Dell Orto, IMHO make not 100 x 'K' series needls but only a handful, then harden them, THEN grind them down into shape and polish. that is why you can see the codes are clearly added afterwards.

THIS MEANS YOU CAN RUB A LOT OF MATERIAL OFF. THERE'S LOTS OF IT.

I use a steel ruler just 12.8mm wide and P400 wet and dry. I use WD40 and have constant use of the vernier. we're talking here of taking NOT a tenth of a MM off but just a HUNDREDTH of a mm off.

I then finish by polishing the needle with Brasso. you can see the tin of Brasso behind me in blue and white. Note in the big photo that the vernier is never far away!

Taffy

If testing and wanting to know which area of the jetting you're in you could do worse than increment the throttle grip like I do here. The Husaberg throttle (standard) works over 45 degrees. you probably think that it is evenly spread but it isn't.

The throttle cam works harder at the beginning and opens the slide further than it does later giving refined low speed throttle control. The 'throttle cam' as it is called, starts 13mm from the inside radius of the grip but ends 17mm from it.

the throttle only just goes to WOT even if you have virtually no slack. so make sure you have virtually no slack! oil and grease the throttle assembly.

I attach a drawing of another throttle cam. having played with the G2 throttle cam I can vouch for how good the correct cam is.

Taffy

https://www.taffmeisters.co.uk/product_info.php?products_id=3491

A nice readable quote here from one of my customers. Thanks to Bastion for reporting in. This is it verbatum;
Quote; “Brilliant kit and advice and expertise from Taffmeister! Solved jerking throttle response, bike bogging and backfire issues for my FE 501 2002. I have yet to complete the last step of the re-jetting/refurb of the Dellorto carb from the Berg Booster Kit (reduce Pilot Jet from 58 to 45 and Pilot Air Jet from 100 to 40) but already a massive difference, night and day, compared to default/factory carb settings.

My issues were: bogging on acceleration and then stalling after 10-15min of riding, would not start again. Jerking and skittish throttle response on acceleration. A lot of deceleration backfire. Uneven power distribution when transitioning through the gears.

Before you buy: Make sure your issues are carb related or this kit might not solve your problems i.e. your engines timing is correct, the valve clearances are in spec, no vacuum or air leaks from carb/cylinder/exhaust etc, carb is receiving enough fuel, float height is correct and that you have spark!

More detail: My Dellorto had 38 Pilot Jet and not the standard 35 Pilot Jet, everything else was factory settings. The carb was cleaned thoroughly had no blocked jets or passageways. Fiddled with float height and needle clip settings but nothing solved the bikes issues. I installed the Berg Booster Kit and I am now singing and dancing. Installation of jets, needle, etc. was very straight forward. Increasing the mouth of the slide (4mm to 6.5mm) requires a bit more courage but nothing insurmountable. You will need a vice, a metal file, a Vernier calliper (I used a digital one), wet and dry sandpaper (P400 with WD40), steady hands and patience, as you do not want to rush this step. After installation the bike initially did not want to start, even with choke (I have the manual choke leaver next to the clutch leaver). Fuel Screw was at 1 turn out and Idle Screw was on 0 (not affecting slide height). I then started turning the Idle Screw in by half turn increments. Got some response after 2 turns in. Bike started easily on 3 turns in with a bit of choke. Currently runs smoothly with Fuel Screw on 0.5 turns out, Idle Screw on 2.5 turns in, Pilot Jet 58, Pilot Air Jet 100, Main Jet 185, Needle Clip on 7 (nearest to the tip/bottom of needle). I live right next to the ocean and did this on a cold dry winters day in December. I expect Idle Screw and Fuel Screw settings to slightly change for the summer and perhaps Needle Clip set to 6 (a bit leaner) rather than 7 (richest setting). I still have to change the Pilot Jet to 45 and reduce Pilot Air Jet to 40, to further improve fuel consumption and fine tune the bike (not an absolutely necessary step but why wouldn’t you!?). Thanks again to Taffmeister for putting in all the initial hard work, for creating this carb tuning kit, all the advice and tips and tricks given via telephone!”

cheers

Taffy

Thought you were retiring, Taf?! Working on Xmas eve?! Hope you had a good one!!!
Rik