Project; Turbo GSXR Slingshot

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So cold starting is getting better, needs very little extra fuel.
Also starts reliably at a good range of temps.

Seems a little fluffy at steady low rpms but even slight load cures that.
Also need to wear ear plugs, its a bit unsociable....
 
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Managed about 250 miles over the weekend. Took it in the van up to Keswick where I met a couple of mates and rode with them up to Moffat leaving the gf to drive the van up.

Had a good 150 mile ride out on Saturday as well, both rides had mostly rain and hardly any dry roads so it was a good shakedown weekend.


Found a problem before we even set off from Keswick, with the lights on and idling the alternator doesn't produce enough power and drains the battery!

Also the same when the fan kicks in, battery voltage drops to 11.9v on idle.

Its fine once revs pick up but I could do with more power at low rpm.


Only other problem was the little rubber cup over the oil pressure switch, filled with water and shorted out the switch. Killed the bike as soon as I seen it and only took 30 seconds to find the problem but it had me worried while I coasted to a stop.


Got 120 miles to 17 litres of fuel so its a bit thirsty.
 
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There was also a photographer that showed up for a few pics here and there.

20915537_10159280187265201_8468635444618731588_n.jpg


20900937_10159275627040201_6427675196553357043_o.jpg
 
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How's the braking force of that Buell single front disc compared to a more common dual disc / calliper arrangement?

I'd imagine you want some pretty serious stopping power with that power arrangement!
 
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Brakes are pretty damn good, don't normally brake really hard but I tried a few emergency stops if you like and it pulls up very quickly.
Much better than the standard 1100 but don't know how it compares to modern bikes.

Need some stronger adjuster bolts on the swing arm, even with the wheel spindle FT it bends the adjuster bolt on the chain side.
 
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Any updates @Danm54 ? Must be nearly done now :p

Its taken a back seat over the winter to be honest.
Sadly Dan Hegarty died at Macau last year so tuning stopped then and I've not touched it since.

I've found a local guy that has a dyno and has played with forced induction in the past so its booked in for a base run on Friday. Will go into ignition timing with him and may also play with the cam timing too, its very loud currently and I think thats down to cam timing.

Will keep you updated.
 
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7 years after I started this thread, here's a dyno graph!

20180601_095440.jpg


With some air temp and humidity corrections the next pull was 198bhp. Think the slight dip is where its running a little rich, will go more into it on the next run.

The line at the bottom is drivetrain/transmission drag which max at 15bhp so its 213bhp at the crank.

Lost 2 header bolts so I need some lock washers or I might find some locking tabs and use hex heads instead.

Mark said to put the intake cam at 110 degrees lobe centre and see how that affects it. In theory it should make a little more power and run smoother at lower rpm.
 
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7 years :eek: That’s some dedication keeping the project going that long, especially with so many twists and turns!

213hp at the crank is good going, have you had a chance to see what it’s like on the road with that power?
 
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Yes I've done a few miles on it, went to Scotland for a couple of days last year so took it up most of the way in the van then went on a few ride outs.
Its had a few trips out locally as well.

Surprisingly it's quite easy to ride, the power comes in smooth and controllable but obviously its damn quick.
Was looking through the ecu stats last night and its spent most of its time between 5-20% throttle. Need to change that this year.
 
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Yes I've done a few miles on it, went to Scotland for a couple of days last year so took it up most of the way in the van then went on a few ride outs.
Its had a few trips out locally as well.

Surprisingly it's quite easy to ride, the power comes in smooth and controllable but obviously its damn quick.
Was looking through the ecu stats last night and its spent most of its time between 5-20% throttle. Need to change that this year.
Hi.
I just read whole topic and I have to admit you've done amazing job.

Would you mind sharing your tuning files?

I have a plan to build 1216cc turbo with Microsquirt,
I also have a project making a 749cc to ~1004cc without turbo but fuel injection.
 
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Hi.
I just read whole topic and I have to admit you've done amazing job.

Would you mind sharing your tuning files?

I have a plan to build 1216cc turbo with Microsquirt,
I also have a project making a 749cc to ~1004cc without turbo but fuel injection.

The Microsquirt never really had any tuning as it was so intermittent and unreliable. I've since bench tested it and it powers up and connects to the tuning software so I'm not sure how broke it really was.
 
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Torque is pretty good, otherwise the figures aren't as high as I was expecting

I was expecting around 250 to be honest, I think there is still more to be had as it's only the fuel map thats been tuned so far.
There's still cam and ignition timing plus acceleration fueling to set as well.

I've actually set the fuel map to MAP vs RPM instead of TPS vs RPM.

There were areas higher in the rev range where if you held the throttle steady and the turbo spooled down, it would run really rich when you opened the throttle again.

MAP vs RPM should eliminate this and with acceleration fuelling set up it shouldn't hesitate when you open the throttle. Thats the next step anyway but as usual finding someone with a dyno is the problem.
I'm looking at making an inertia dyno that will help me do most of my tuning at home.

A house move is currently taking priority so most projects are on hold at the moment.
 
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