Suzuki DR800 fuel injection project

I will try to put fuel injection on my -92 DR800 during the winter.
This is the first time I install FI so I'm a bit anxious. There is a few success stories on the internet with FI on thumpers so it should be possible to get quite good results. Only considering cost and hours spent in the garage I guess a set of flatslide carbs would be far easier and cheaper but I've wanted to learn about FI for a long time and this seem to be a nice project to start with.

Thought I'd post it here in case someone else is interested....and to add some pressure to get things done

It has been quite a few questions regarding the final setup, so I decided to add some coments to the partslist below to sum things up a bit (marked yellow Edit)

The parts I'm going to use:
ECU: Microsquirt
- contol the fuel and leave the ignition stock for now.
Edit: Fried two circuits on the microsquirt so ended up with megasquirt. Three times as big but it is a DIY kit so easier to mod and repair later. Works really well so far.

Fuel pump: Honda TRX 680 ATV
- low amps, but a bit low on flow too. Should theoreticaly be ok for around 70hp. Another option is the inline pumps of Moto Guzzies.
Edit: The TRX pump didn't have enough flow. I could not find any leaks, so I guess the pressure/flow was too low. Ended up with a modified GSXR1000 in-tank unit with fireblade filter instead and it is night and day, almost too much fuel now. Don't seem to draw much current either.

TB and injectors: 2004 R6
- they are big (38mm) but I think they will be ok because of the CV-carb style slides. Have concidered TB's from other inline fours as well but I don't think the microsqiurt will be able to drive the stepper-controlled butterflies. R6 injectors are about 250cc/min@43psi so two of them should be ok. There seem to be four separate TB's so I'm hoping to remove the two in the middle and be good to go with TPS and throttle cable on the two outer ones. I've also tried TB's from SV650 and a single one from Ducati 916, but SV is too much work to place side-by-side and the 916 unit hit the frame.
Edit: The R6 TB's and injectors is ok, but you need adapters for them to fit. Found out that GSXR600 01-03 TB's could be squeezed into the original intake rubbers and they are four single units linked together, so easy to space two of them out to fit the DR.

TPS: Stock R6
Edit: Stock GSXR600

IAT (intake air temp): GM open type from DIYAutotune

CLT (coolant temp): GM closed type from DIYAutotune
- will try to make an adapter and fit it between engine and oil-line to the top.
Edit: This setup had a lot of delay and did not really say much about the real head temprature which is important during warm-up and warm starts. I made my own version of a Ducati sensor mounted in the front walve cover, a 8mm brass plug with an NTC element inside. It responds fast to temprature changes and it was easy to set up the resistance values in Tunerstudio.

O2: Wideband Inovate LC-1.
- think it will be almost impossible to tune this thing without one. Combined with the logviewer software it should be able to get things going.
Edit: I will say that a wideband sensor is a "must have" if you start tuning from scratch. You could do a lot of damage if you start pushing the engine with a lean mixture and it really helped me understand what was going on. Good manual and the values for the LC-1 are pre-programmed in Tunerstudio.

MAP: 2,5 bar GM
- not sure if I'll use this yet. Have to measure the vacuum pulses before i decide on MAP or alpha-N.

Airfilter: Two universal UNI filters

Exhaust: 47mm stainless in front of and under the engine + Laser proDuro
- I've seen that some recomend 2" pipe, but that looks realy big compared to stock. I'm afraid I will loose low and mid-range power and torque(?) The port in the cylinder isn't that big either. If someone have some experience with this any advice would be appreciated.

The plan now is to measure the vacuum with the carbs on and decide MAP or alpha-N, maybe a blend with alpha-N for idle/low rpm.
Edit: The mapsensor works fine, but the signal is a bit erratic and the values goes to atmosphere pressure too soon so it is no good for tuning other than give you an idea about load/no load. The range during riding is 75-100 and it goes down to 35 when you go off the throttle. Ended up with alpha-n and it works fine. A bit of trial and error to find the right spacing on the axis in the tables for a smooth throttle on/off but other than that it has been ok. The live analyzer in Tunerstudio is also a really useful tool, saved me a lot of time to get a rough VE table.

I've designed new intakes for the R6 TB's and adaptor for the CLT sensor. Fortunately I have a friend which has access to a CNC mill...just have to be patient and wait for him to finish.
I'll try to mount the IAT sensor somewhere near the airfilters.
The fuelpump assembly is quite big (it sits in a reservoir), and might be a bit difficult to mount but I'll try to fit it where the airbox used to be.

Will try to post some pictures later.

Amund

interesting project Good Luck with it
I look forward to reading about your progress

me too...and as i have a dr800, i would be interested in buying a kit following a success story and your willingness to go commercial

Count me in.

Cool project! Definitely keep us updated how it works out.

http://www.thumpertalk.com/forum/showthread.php?t=455497&highlight=winter+project+fi

read that thread. HE did the same thing with a dr350 and megasquirt with good success.

Pick up the book on FI by Adam Wade.

Have you considered a TB from a BMW? Specifically an F650 or an oilhead. The only issue that I see is that they don't have linear (3 wire) TPS.

Thank you for all the replies and tips Really cool to see that so many others are interested.

The Adam Wade book is already in my bookshelf . I agree, great book with a lot of useful info.

Drhach: Thanks a lot! I just found out that the F650 has a nice and small external fuel pump. Seems to deliver 150l/h so think I'll try to find the Bosch part # and use it instead of the TRX. I have considered BMW TB's but have decided to go with dual ones because of the small space behind the cylinder...and it is more complicated to machine a new manifold as the DR800 originally has dual carbs.

EDIT: Checked with BMW dealer about the fuel pump. Turns out the part that was refered to as pump on the website is acutally just he fuel FILTER.

Regarding a kit...I haven't thought that far yet. For sure I'm going to share all the technical stuff here, all the parts, issues that might come etc. The tuning file for the MS is a bit different. I'll get back to it IF i get things working

ambraa....would it be possible to use the original carbs as TBs and just fabricate injector and TP mounting points?

Maybe it is possible to use the carbs, but i think it will require a lot of work. Probably a lot more than making new intakes for the R6 TB's (might be different if I didn't have access to the CNC mill). It is also practical to have all the mounts, fuel rail, injectors etc matched together...and the R6 TB's are quite common on ebay.

The DR800 is a twin isn't it? I guess I had a brain fart, I was lumping it in with the DR650 which is a single.

No it's a single. But it has dual carbs.

If somebody wanted to do the same thing on a DR650 they could use the head off a European XF650 Freewind as it has dual inlets as well.

Just saying... Would be nice if somebody was the test rabbit so I can just copy the final working result.

I finally got time to modify the TB's. It was quite simple, removed the hoses, fuel rail ++ and the two long bolts through the four separate TB's. I mounted the outer ones together with shorter bolts, cut and welded the fuel rail and then they look like this: PICTURES

Also added some pictures of the fuel pump.

Hope to connect the pump and TB to test for leaks during the weekend.

I have some trouble getting a correct RPM reading from the VR sensor on the bike, but got a few tips today so I hope it will be sorted pretty soon.

I was considering doing this on my elefant. I read something about a guy that used a microsquirt to replace the computer on his 1150gs. He had it setup so he could change his fuel tables and such with his palm pilot.

Some of the DIY fuel injection systems I have looked into(For a hotrod project) have a self learn function. You put in some generic fuel tables and it will correct them when in the tune setting. I ended up getting a link 4 system but have had to put it on the back burner untill I get some more time.

Very cool, please keep us updated.

-John

Last night I tested the sensors and fixed the rpm signal problem. The RPM on the MS was twice that of the tacho on the bike. Changing the settings in Tunerstudio to 2 cylinders with simultaneous 1 squirt solved it.

A couple of PICTURES.

thank you ambraa for keeping us posted with your progress.
I recently came across ths product:

www.afrtuner.com

and thought you might be interested.