GSX750ET Race Build

[Pete750ET]

This the adaptor plate to connect the oil cooler to the filter housing.
Can give you dimensions if you need them.
I lent it to someone who measured it up and was going to reverse engineer some, but can't think who it was now?
You might be able to weld two bosses to the existing cover and fit adaptors for the hoses?

Edited November 9, 2016 by Pete750ET

[Jelly]

Very curious, any updates on the bike @maxwin?

[maxwin]

Funny you should ask @Jelly...

Update time

Firstly, I decided to try dialling the cams as I've been told that this can give a few bhp's for very little investment (money that is, it's very time consuming), and it turns out it was good advice.  I set the valve adjusters as per the book with a feeler gauge and then got out the DTI made a degree wheel and measured all the valve opening durations, to my surprise the duration was out by about 15 degrees either side of spec so the valves were open too long.  After a day of dialling I'm pleased to say the performance has greatly improved, especially on start up and idle, and no more fuel mist blowing out of the bell mouths.

Next up I purchased a set of Gazi hyper X shocks for the rear, compared to the Koni emulsion tube ones I had before there is no contest.  The rear of the bike is so planted now even when cranked right over, I would highly recommend them though they are a little pricey at 600 quid but still way cheaper than Ohlins or Nitron.

To combat ground clearance I decided to make new engine brackets and raised the engine 25mm, so it now sits jammed up under the tank, only draw back is that I need to remove the tank to get the plugs out which is only a 2 minute job to be fair.

Wheels have been changed for 17" GSXR400 ones, I'm running a 110 front and a 140 rear.  I changed to Dunlop Alpha 13 SP tyres which are effing amazing much better than the Avon AM series tyres that I had before.  The bike feels light and nimble and can be flicked left and right very quickly without any wobble or uncertainty.

Solved the fuel surge problem and at the same time lost 10kg on the bikes starting weight by filling the tank with fuel tank foam, bought a job lot of off cuts off Eblag for 18 quid, money well spent lol.  Before I would have to start the race with a brimmed tank or it would surge big time under the heavy braking by the end, now instead of 20 litres I can get around with a mere 7  

Some action pics.

Lodge Corner at Oulton Park last Saturday...

Esses at Mallory Last Sunday...

Devil's elbow at Mallory Park...

Another Devil's elbow, you can clearly see I fitted the OSS stickers upside down... maybe time for some winged ones

Managed a first place at Mallory which I was well happy with, I'll upload the videos to youtube at the weekend.

On the to do list is an oil cooler as Pete has said above, the power seems to fade by the end of a race and the bike idles like an old diesel

The swingarm is going to get beefed up, I'll tig weld some 30x10 flat to the top and bottom to make it more rigid.  On full speed bends with wide open throttle there is a bit of weave developing so hopefully this will cure that.

Also going to fab up a new gear lever and linkage as the current one has loads of play and I've missed a few gears lately, which is unacceptable!

Thanks for reading, more to come.

[Gammaboy]

With lifting the motor, did you fab new brackets for the lower rear mounts? or just rotate the motor around the lower rear?

[maxwin]

@Gammaboy I'll take some pictures today, but short story is I brazed on some extensions (bit crappy atm) so the whole thing has been lifted 25mm.

Chain fowled inside the chain guard so there was a small alteration there too.

[Swiss Toni]

Great build thread, great video's, and you've got a good right to feel smug about your seat. I would too!

[Jelly]

Good effort @maxwin, my (street) ET has a oil cooler conversion just as @Pete750ET is showing above. Will take some pics of that tomorrow and post them here for reference. Don't have any drawings on it. 

And regarding the stickers, I'm sure @minx can help you with some! 

[KATANAMANGLER]

@maxwin take a look here.We have some very special stickers for racers. PM and let me know if you are interested

[maxwin]

As promised here is a short race report and vid of race 2 at Oulton park last Saturday.

I've never been to Oulton Park before so binge watched as many youtube clips as I could stomach to help prepare me for the longest and arguably most complicated track in the UK.  Due to work commitments I couldn't make the test day on Friday so had to learn fast on Saturday, did plenty of grass tracking on the practise and also did a bit on race 1 too ;).

Club/Class: Formula Prostocks Racing / FP2 Post Classics

Event Organiser: North Gloucester Road Racing Club

After collecting my thoughts over lunchtime and talking through the problem areas with my dad I felt ready to put it together and have a crack at a reasonable race result.  Finishing 12th on race 1 put me 12th on the grid of 32, not a great position as its on the inside line, on race start everyone seems to flock to the inside and get all bunched up (you can pass a lot of people by hanging out wide).

After a reasonable start, I stuffed poor Andreas Jelden on his FZ into the first chicane (out braked myself).  Couldn't get Druids corner right at all, always scrubbed off way to much speed, this was exasperated after the high speed weave on lap 3 around the Water Tower.  Cascades was another area where I felt slow, need to build a bit more confidence down the hill around Denton's.  Andreas managed to out brake me into Hislop's chicane on the last lap so I settled for 6th overall, back on the 22nd of April with Earlystocks and feeling quietly confident for a top 3

Enjoy the vid, I certainly enjoyed making it!

 

[gsx]

Brilliant , loved watching that .

My old 750 never went that well !

[Pete750ET]

Great video, takes me back to racing my GSX750 with the Earlystocks, funnily enough running #230 as well.

[Jelly]

Same plate as above used, didn't build it myself. Bike's in the lockup now so it looks a bit greasy, but you get the idea:

[maxwin]

Wanted to get the gear shift sorted before next weekends return to Oulton, the current set up was cobbled together from an old SRAD lever and linkage and never worked particularly well...

I decided to have the new one pivot on the foot peg and better line up the linkage, also the old rod eyes have loads of play in them.

Roughed out a design on some 10mm ally plate and carved it out on the mill...

Bored out the bearing hole on the lathe...

neatened up the rough edges...

and as I hate polishing I used the mill to skim a few thou off...

and all fitted up nicely, much less backlash and the operation is loads easier.

Toe spigot is just an 8mm bolt with some self fusing rubber tape

[Solcambs]

I hate watching race vids ... It reminds me how much I miss racing, and how little I can afford it nowadays! Age and other commitments get in the way sometimes - So quite happy to relive previous days vicariously. That Oulton vid really does allow you to hear the difference in the motor. Much cleaner since the dialling in you did. Likewise it seems to hold a line way better, and definitely looks more planted.

Anyhow  @maxwin ... I look forward to reading about your exploits in the winged hammers section.

[Jelly]

Spotted by a Practical sportsbikes member on Oulton park last week:

[maxwin]

Well...

The thrills and spills of my second outing to Oulton Park.

Qualifying went really well, put in a new personal best and got pole position for race 1.  All the parts of the track where I had felt slow last time I had improved this time round, felt like it was all coming together...

Race 1 start, I was over taken by the #2 Moriwaki Kawasaki of Nick Allison off the line but managed to sneak around the outside of him in turn one, I led the race for 5 of the 6 laps with a healthy 14 second lead on 2nd place, also set a new personal best and a club record of 2:00:653.  Unfortunately I didn't know I was in for a comfortable win so kept pressing on and High sided out of Lodge corner at a respectable 54mph

There was a lot of tumbling and no sliding so I feel like I've taken a ride in a giant washing machine on full spin, but thankfully nothing broken.  The left forearm of my leathers split which has left me with a bit of gravel rash.

Bike almost went over as the top of the tank and fork tops have been damaged but luckily it failed to flip and slid on the left side. Didn't put any oil down either which is always nice.

The biggest disappointment apart from missing out on a fist place cap  is that the GoPro didn't record!

Spares are on order, have Donnington on the 13th and 14th so need to get busy.

Track day on Friday at Cadwell to try out the new 600SRAD so that will be my getting back on the horse outing

I'll post some pics soon of the damage and the repairs.

[vizman]

14 second lead on 2nd place....still pushing.....

 

 

[stockcar]

You need some better pit signals....... 

Edited April 27, 2017 by stockcar

[Solcambs]

On ‎24‎/‎04‎/‎2017 at 4:20 PM, maxwin said:

my leathers split which has left me with a bit of gravel rash

14 secs over 2nd place ... were you pushing :o) With regards the leathers - get rid of those Alpinestars - as you've found out, anyone who has every raced in them never buys a second pair!

Not sure who does leathers that are worth their weight anymore - I always had Crowtrees which survived several years of racing and sliding until they were cut off me :o( I replaced them with hideout leathers - which I've still got and are respectably scuffed to buggery and still holding together very well. As for off the shelf leathers you can race in, takle a look round the paddock at what others are wearing and crashing in ;o) 

[vizman]

i guess most protective wear these days are designed to do the job once....and do it well.

i see a lot of them cray-zee irish road racers wearing scott leathers that look used and abused.

[Solcambs]

1 hour ago, vizman said:

i guess most protective wear these days are designed to do the job once....and do it well.

i see a lot of them cray-zee irish road racers wearing scott leathers that look used and abused.

Scott and Wolf leathers IIRC had good reps back in the day when I raced. If I go to the track, I want the best cost/performance for the inevitable slide and ragdoll. If you race, it's not if, its when!

The requirements at the track are different really - at the track (vs the road), there's less chance of impact and puncture injury - but there is a much higher abrasive related risk, so the leather thickness abrasion resistance (and leather type, 3 layer stitching, etc) is very important. 

I know a chap who has been campaigning to change the leathers quality measures for years (with some success) ... his pet peeve is Alpinestar's use of the regs to get away (in his opinion) blue murder. Their interpretation of the regs allow them to get away with leathers that aren't reallt fit for purpose. The quality, type, and thickness of the leather and the way they bond and stitch their leathers is an source of open criticism IIRC. Anecdotally, the are known to abrade poorly, and often burst seams.

Anyhow ... it's a matter of personal choice. I, for my part, wouldn't want to race in anything allegedly substandard for the road, never mind take them to a race meet ... It's a moot point though, as I don't race anymore, and I'm fortunate enough to still have a good fitting set of leathers that I trust for trackdays.

[Gammaboy]

On 28/04/2017 at 10:47 PM, Solcambs said:

 Alpinestar's use of the regs to get away (in his opinion) blue murder. Their interpretation of the regs allow them to get away with leathers that aren't reallt fit for purpose. The quality, type, and thickness of the leather and the way they bond and stitch their leathers is an source of open criticism IIRC. Anecdotally, the are known to abrade poorly, and often burst seams.

Sounds alot like the shit run I had with Alpinestars gloves. fucking things.

[Fugly]

Check out Jay Dexter on facebook as he makes made to measure race leathers for a lot of the supermoto guys, not seen the grade of leather he uses but has a good rep amongst these guys.

 

[maxwin]

Oulton Update.

So judging by the comments not a lot of love for Alpinestars lol, but to be honest I bought those before I knew I would start racing and only because they looked good.  Knowing what I know now I wouldn't buy them again, my next purchase would be a set of Scott's probably with my race number on them

Here is a GIF of the crash from all the pics I got of it...

And a few pics of the crash developing, I remember deciding to eject when the bike started to slide, having high sided before I no longer feel the need to try to hero save it

I've had the leathers repaired for now as funds are a little tight, I'm running the SRAD with the GSX at Cadwell in a few weeks time and the setup cost for the SRAD has cleaned me out!

Repairs have been a bit of a bodge up, just enough to get back out again.

Donington write up to follow...

Edited May 19, 2017 by maxwin

[Jelly]

Confronting images, but hey, at least the OSS logo is clearly visible while sliding