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XR650R EFI crank trigger wheel idea?

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SO im starting to get into needing a way to get crank angle on the XRR's future EFI install. WHat i would like to do is grind off the stock flywheels single tooth and get like a 12 and 1 trigger wheel made to press or weld in the stock plane of rotation for the stock sensor crank sensor.

Those in the EFI know, would this be possible? what kind of sensor is the stock pickup? hall effect or some other? would there be a better way?

my plan is to use the microsquirt for fuel and ignition on this and the cam sensor is looking to be the easy setup but i dont have the means to make a trigger wheel myself so any help is appreciate.

z

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I'm pretty sure that the sensor is the variable reluctance type. It has a magnet and coil of wire in it. When the "tooth" swings by it makes a better magnetic circuit and a pulse of current is generated.

Welding and then machining the stator seems like a lot of work. Here is an idea of something that might be a little easier without a machine shop. Since all that is needed is some iron that passes close to the sensor how about some small bolts or set screws? Drill and tap some holes in the outside of the stator and using red locktite screw in your "teeth." Not sure how to get that kind of setup balanced correctly though.

Hey it's just an idea...

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Paging Captain Midnight...

heres to hopin' him and headtrauma

I'm thinking something like a thinwalled reluctor shrunken over the flywheel.

why speak of the devil, thats kind of what i was hoping to do and just utilize the stock sensor. basically machining the single "tooth" off that the XRR has and installing the toothed ring in that spot.

http://www.thumpertalk.com/forum/showpost.php?p=10739696&postcount=31

For an L, but if he makes 'em for one maybe he'll make one for an R.

Dave

THanks iv seen it read it and others like the DR DRZ and other EFI projects guys have i simply just dont have the machines capable of creating one.

maybe some one who does here can for me and i can compensate them gladly :thumbsup:

z

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Since you'll be using a MicroSquirt and will have a fairly large reluctor if you use the flywheel, I would suggest a 36-1 wheel for even higher crank angle resolution. This is especially useful with singles because the crank speed varies quite a lot between combustion events at lower RPM. 12-1 will still work pretty well, but the MS-II processor has plenty of overhead for the extra teeth and the RPM that a 650R will see. You could even put a second single trigger/sensor on the cam for "sequential" injection and spark. This will also allow the processor to sample manifold pressure at a specific point in the engine's cycle(which MS-I can't do). Without doing that, the MAP signal will oscillate significantly at lower engine speeds, probably by at least 20kPa and the MS won't like it unless you do something to dampen those oscillations. Here is an example from a single-cylinder engine running MS-I:

6d9097a0.gif

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a 1/4 inch needle valve with hose barbs makes an ajustable method of dampening those intake pulses to make it possible for the megajolt vacuum gage to be readable with little bounce.

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a 1/4 inch needle valve with hose barbs makes an adjustable method of dampening those intake pulses to make it possible for the megajolt vacuum gage to be readable with little bounce.

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Since you'll be using a MicroSquirt and will have a fairly large reluctor if you use the flywheel, I would suggest a 36-1 wheel for even higher crank angle resolution. This is especially useful with singles because the crank speed varies quite a lot between combustion events at lower RPM. 12-1 will still work pretty well, but the MS-II processor has plenty of overhead for the extra teeth and the RPM that a 650R will see. You could even put a second single trigger/sensor on the cam for "sequential" injection and spark. This will also allow the processor to sample manifold pressure at a specific point in the engine's cycle(which MS-I can't do). Without doing that, the MAP signal will oscillate significantly at lower engine speeds, probably by at least 20kPa and the MS won't like it unless you do something to dampen those oscillations. Here is an example from a single-cylinder engine running MS-I:

IMG]http://img.photobucket.com/albums/v521/65ShelbyClone/Public/6d9097a0.gif[/img]

I knew about most but being able to take your reading at a certain degree will definitely ease the tuning inthe lower rpm ranges. i was hoping to get the v3 microsquirt but they have said the projected release is now unknown so ill probably find a v2 and get rolling on this.

I was under the impression that the larger number of teeth the slower the microsquirt became because of the amount of calculations being made. Is that not so much of an issue only running one cylinder compared to multi cylinder setups?

a 1/4 inch needle valve with hose barbs makes an ajustable method of dampening those intake pulses to make it possible for the megajolt vacuum gage to be readable with little bounce.

not a bad idea, have the small orifice to limit wide pulse differences. other ways iv read are pulse chambers (larger air chambers in line) or an oil filled tube.

Is that Arkansas slang? LMAO.

All this info being shared and this is your contribution..... :thumbsup:

Captain Midnight ill shoot you a PM.

z

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I was under the impression that the larger number of teeth the slower the microsquirt became because of the amount of calculations being made. Is that not so much of an issue only running one cylinder compared to multi cylinder setups?

That is the $64,000 question. I have not been able to find any reliable information on situations where any of the MegaSquirts run out of processor. The MS-I is quick enough at 8mHz(late 1980s speed) to keep up with 16,000rpm controlling fuel only and the MS-II has twice the clock speed. Unfortunately i do now know how that translates when using more complex code like MS2-Extra.

not a bad idea, have the small orifice to limit wide pulse differences. other ways iv read are pulse chambers (larger air chambers in line) or an oil filled tube.

That datalog I showed was with a 2x3" fuel filter in the MAP line. :thumbsup: Just remember anything that dampens the pressure swing will also affect sensor response.

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As usual Captain Midnight shows some more mechanical beauty.

For a bit of a hijack question, what would be a ballpark cost associated with a getting one of these setups going? Using an ebay throttle body and fuel pump, junkyard sensors, and whatever else to lower the total.

Edited by cleonard

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As usual Captain Midnight show some more mechanical beauty.

For a bit of a hijack question, what would be a ballpark cost associated with a getting one of these setups going? Using an ebay throttle body and fuel pump, junkyard sensors, and whatever else to lower the total.

Well i picked up a tl1000 throttle body setup for 40shipped on ebay and others have said they can get kx450 fuel pump for 40-60$ but i havent been able to find one under 120+. a few junkyard GM sensors wouldnt cost much and then the price you can get a microsquirt for. and pending your ability to get the sensor ring made or pay for that.

probably around $700 im looking at almost 1200 for what I consider acceptable (new sensors, wire, computer, and weather pack connections for a very OEM look and troubleshootability) I dont like trying to find wires in a rats nest and my setup will be for a street only turbo setup i want it to look good and perform even better. :thumbsup:

z

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I think you can do it for a little less. Microsquirt Module $250. Ebay throttle body $40. Sensors $5. Pull-A-Part fuel pump $20. Solid State fuel pump regulator $50. Innovate LC-1 Digital Wideband O2 sensor $200.

microsquirtmodule.jpg

Wireharness2.jpg

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Hey Ya'll,

I see there is a Trx700xx throttle boby on eBay every now and then. Would this be a good throttle body for a Xrr conversion? Any thoughts? Thanks, Tony

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Yes, it would work fine. Most all of them will. Find something that has a size and shape to fit in where your going to install it. Don't pay alot for it, they can be found pretty cheap.

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OK since this started there has been another guy looking to do a EFI XRR and created a CAD file for a 24 tooth flywheel trigger wheel to be pressed on. He Emailed me the file and im going to be getting the wheel cut out at a stateside CNC shop hopefully wont cost too much but i think im going to get at least 2 made. ANy suggestiond on material thickness i was thinking 3/16-1/4" mild steel.

Oh and the guy doing the other EFI XRR's thread got lost as he made it during the move unfortunatly and all my PM's i think his name was marty or martin something here on TT.

z

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