if i use an r1 do you have to use exup?
the exup valve is there to regulate back pressure. this is to increase performance and to reduce emissions. i think the engine will run without it but
there may be some complications on the wiring side.
as an aside, R1 users rarely mention the exup valve, so maybe this is a sign that it isnt used.
Nope. Evidently there's a mod you can do to stop the error code appearing on the dash which Im sure Paul (Rogers) will know, but it can be junked.
do people junk it because back pressure helps low end torque and they are after top end power?
you don't have to use it, you can just plug it into the loom but not attach the cables, if you dont plug it in to the loom though you get a fault
code on the R1 clocks (if your using them).
I think there's a way to fool the cdi into thinking there's one fitted - I think you fit a resistor but not sure.
HTH
Colin
Doh...beat me to it!
[Edited on 4/2/05 by colibriman]
can't do it with a resistor. There was a site "bikeenginetransplant" or something like that with a complex "exup pretender"
circuit in. I've got a much simpler idea using a cheap optotransistor, a transistor and a capacitor which I'll try when engine start time
comes, when I make it work I'll publish but don't hold your breath...
If someone wants to try & debug it for me get in touch!!!
Cheers
Bob C
by 'debug do you mean try it to see if anything goes up in smoke?
http://biketransplant.tripod.com
[Edited on 4-2-05 by mangogrooveworkshop]
http://www.jbracing.co.uk/Details.cfm?ProdID=39
Its more expensive than a exup valve!
[Edited on 4-2-05 by mangogrooveworkshop]
I made one up from the biketransplant site and it worked no problem at all, It must of cost me about 20 quid tops, I wondered if it was worth making
these for others- would there be a demand?
Andy
>>>by 'debug do you mean try it to see if anything goes up in smoke?
pretty much! Excellent - so I have a volunteer then!!
Actually someone with a working BEC would make the best test vehicle.
It shouldn't be able to cause any smoke really.......
t'would be a tiny little thing that would be built into the loom plug.
Cheers
Bob
hmmmm......
before after 
due to the flash, bang, smokin effect
Hi All,
You can definitely get rid of the EXUP and still keep the original clocks. If you short the red/white wires the only time you will get the fault
indication (tacho bouncing between 0 and 6k revs I think) is when the ignition is on but the engine if off.
All other conditions (engine running or in any gear) there is no interference with the tacho function.
See http://www.samannasystems.com/chart.html
Why get rid of the EXUP? you can get better torque and power without it - don't forget most BECs have custom intakes and exhausts so you can take
advantage of this to improve on the basic 4-1 exhaust and airbox that Yamaha used. 160hp is easy to get with better intake, exhaust and a rejet.
Cheers
Paul
Cool...thats handy to know....cheers Paul
quote:
Originally posted by progers
You can definitely get rid of the EXUP and still keep the original clocks. If you short the red/white wires the only time you will get the fault indication (tacho bouncing between 0 and 6k revs I think) is when the ignition is on but the engine if off.
does this mean that you dont need the servo too???????????????or is the servo still to be used????????
My servo cost me £20, so I should have no fault code problems! 
One tip though - don't bothr using the valve as they were developed to get the bikes through the homologation drive-by noise tests! They have no
effect on bottom end performance whatsoever! I would actually suspect they have an adverse effect in that they possibly do not allow all spent gases
out of the motor at low engine speeds.....
How's progress Ian?
Just to confirm that loss of EXUP does not affect the performance of the engine by putting the ECU into a different mode.
My ex Indy R1 (no EXUP) was measured at 138 rear wheel HP by TTS in Northampton. This equates to 160-165bhp at the crank. A healthy increase over the
standard 150bhp Yamaha quote :-)
You can still connect the servo if you wish, it just adds a few Kgs of unnecessary weight.
By the way, people should also junk the AIS system as all this does is to inject air into the exhaust to help with emissions. It screws up any add-on
SVA CAT exhaust kit too when it comes to measuring emissions. Junk it and just block up the holes that feed into the exhaust ports. Another couple of
Kgs saved!
Cheers
Paul
progers - I'm fitting the servo only as I'm using the R1 clocks and didn't want the fault code to show.... But that's certainly
good news about not giving a fault ignition map! I've heard mixed reports about this, but suspected that there wouldn't be such a thing as,
to be honest, the stock ignition curve is pretty conservative anyway!
Colin - it's coming on well ta! I'm in the middle of sorting out the loom, then got the gearchange linkage to sort (waiting for some paddles
to arrive from Mr Rarity) and then we'll almost be ready to roll! Oh yeah, I'm still in a dilemma of what to do about the diff - do I leave
the 3.89 in for now (14" wheels) and see just how undergeared it is, do I bite the bullet and get a 3.54 Quaife ATB that I've been offered,
do I pick up a 3.54 open diff and wish I'd bought the ATB in a few months time, or do I buy a cheap set is 15" rear wheels?
Would you believe I missed a 3.54 from Marc by two days? D'OH!!!!!
Why would you wona get rid of the EXUp????
Cos its a great hunk of metal that would sit out somewhere along side the passenger for all to see if installed on a Locost style BEC?
Its only there to improve mid range slightly anyway, top end isnt affected and with a decent exhaust design you dont lose any mid range either.
I can see what you mean about the look of it.
But as for power.The % of midrange throttle is higher on the road ( and some race tracks ) than the % of full throttle and should than be faster ?
Do you not agree?
Jason
I dont know of any kit car that's actually used it so I guess its a bit hard to compare, but a lot of the bike tuning companies bin it when they tune the R1s so it can't be that beneficial IMHO.
I think tunners like to show big numbers on the dyno to people who are spending becouse the 1st thing people ask is whats the BHP.
Jason
i read a website that said if you fit a 4-2-1 exhaust system it brings back the lower end power that you lose by not using the exup valve.
but with the exup motor i had mixed feelings,heard so many stories about it making a difference or it not making a difference that i ended up using
the motor becouse i wasnt bothered about the weight
quote:
Originally posted by short track 123
I think tunners like to show big numbers on the dyno to people who are spending becouse the 1st thing people ask is whats the BHP.
Jason
I've seen them on F1 cars to improve midrange.But then again they can sort the software to get the thing to open when it needs to.
If you know of any one who can sort the software on the Yam ECU let me know.
And i will put 1 on a dyno and see what
happens.
I know some people with bikes that would be intrested as well.
Jason
See Paul's comments above, there's appears to be no need to sort the software in the Yam ECU if you disconnect it unless you need to use the
dash as a dash.
Ive not noticed anything like that on an F1 car before, have you got any pics? The F1 exhausts Ive seen (when they show them on the dyno or on a stand
at Autosport etc) are usually only about 50cm long and of a regular design coming straight out the bodywork sidepods almost as soon as they go into
the collector, I would have thought an EXUP type valve would rob them of too much top end to be worthwhile but I might be wrong.
At the end of the day the BECs seem to perform well enough with no lack of mid range without them, the british superbikes don't use them as far
as Im aware so for me there seems little point making the exhaust look like a dogs breakfast and then not significantly gain anything
cheers
Chris
[Edited on 28/4/05 by ChrisGamlin]
Have no pic's i would get the sack.They didn't put them on show engine or in press photo's.Some teams in the 3.5Lt days did have
them.Don't think they are still used.May be not allowed any more? Not up to date with the reg's.
Still i agree a bit of scrap hanging off the side of a car for at best i would think 1 or 2% in the midrange.Not on my car thanks.
Good to torque about these things it gets the grey stuff going.
Jason
Interesting, wonder why they'd want to keep that a secret specifically, its not as if its rocket science technology any more so than the rest of
the engine etc. I guess any team using them would have needed to scrap them when they went to chimney exhausts exiting on the top of the bodywork just
cos there's no space for it?
Hows your R1ot coming along, they look a quite neat little package from what Ive seen in the mags?
[Edited on 28/4/05 by ChrisGamlin]
Hi there, I'm off to stoneleigh this weekend to have a look at the Riot with the alloy zetec in it. Still not sure if to go bike or car engined. I would be interested to here how the build is going also.
Not got the chassis yet only ordered from sylva 2 weeks ago.
But on the drive side have been burning in oil.
Will be using a neat Diff that bolts onto the engine so no chain also has reversing gear built in and it has LSD to boot ( If i could post a pic i
would but computers are realy not my thing )
The engine side of thing I'm going to try some thing different and use a Triumph 3 cyl ( the one with carbs )
I used the engine for some dev work a few year ago it's bit tiered now but new liners,pistons,and rings have been ordered.Mains and big ends i
have a few sets from the dev project and are now in.
It did make some good power and i have a few new things to try ( If it go's bang we'll think again )
cheers
Jason
[Edited on 28/4/05 by short track 123]
Try this one www.jbracing.co.uk they do aR1 exup motor replacement module desisned to trick the ecu that you have a servo fitted prevents the fault
codes,on the rev counter and prevents any restriction to the cdi mapping,they fit it to track bikes to unleash more power.
you now you have to have it ive got one on my gt1,no tacho faults,but yet to drive it on the road.
Good luck regards Simon
Sorry to wee on your fire Evo, but you have just spent £80 on something that will do nothing to enhance the performance of your R1. As I have
mentioned before, the removal of the exup valve will not change any ignition maps (race teams do this all the time - if there was any loss in power
they would notice!). If you notice even on the jbracing site they say "possible" ignition problems. Its marketing bullshit.
The only benefit this device will give you is the removal of "tacho tango" if you use the R1 clocks. As stated before in this thread though,
if you short the exup wires wou will only get an indication on the tacho when the engine is off with ignition switched on, any other time when the
engine is running you will not get any problems at all.
As I said, sorry to give you the bad news but I just want to avoid other people getting ripped off for something that claims to do something it
doesn't. If you you doubt me just ask jbracing for a before and after dyno plot to see the "extra" they get. I'll bet you get
zippo response.
All the best
Paul