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RaceMag
22-11-09, 03:21
I've just purchased a GSXR 750 engine for a 'learner' car in under 750cc formula Libre. I have been told that the std bike carbs do not tolerate such use very well. What do people usually do to make them work well?

Craig Powers
22-11-09, 11:23
I've just purchased a GSXR 750 engine for a 'learner' car in under 750cc formula Libre. I have been told that the std bike carbs do not tolerate such use very well. What do people usually do to make them work well?

Firstly I've no idea whether this is true. I have no knowledge of this engine.

For a couple of seasons I used the standard ZZR CV carbs on my ZZR and they were fine. I fitted a dynojet kit and better air filter. The Dynojet kit consisted of new needles with different taper and also involved drilling a small hole in the carb piston valve to change the carb's damping and improve the responsiveness.

Later I got hold of some Kehein FCR flat slides and they are very responsive. Recommended if you can get some at the right price.

Personally I reckon the standard carbs will be OK, even without the Dynojet kit. The Japenese do things well. They spend millions on R&D. They will be a compromise between max power, torque, responsiveness but at twisty venues thats probably a good thing.

I'd give them a go.

RaceMag
22-11-09, 12:14
Thanks for your input. I'd intended on having a go with them. Locally it was a cheap engine at 500 UK pounds for one with 10,000km on it, but it has been sitting for 4 years so will get a little careful attention.
I'm not that interested in chasing power per se, but am really interested in reliability and driveability. The intent is to make a simple, rugged and very reliable car that is something that can be shared amongst 2-3 drivers on the day. Speed will come later after we have finished scaring the willies out of ourselves!

Craig Powers
22-11-09, 12:24
How much of the installation will be standard? i.e. what's the exhaust.

If you can get the lambda checked then that would be worthwhile. Then you know it isn't too lean. You either need a rolling road or a venue with a straight where you have time to look at a lambda meter. If you can borrow a lambda meter then you can install it temporarily. I don't use mine much.....but it gave me confidence when I installed a standard engine with a new custom exhaust.

RaceMag
22-11-09, 12:34
I have access to a wide band Lambda meter and motec data logger, but we will not be considering actually making the thing until after the end of the year...so exhaust is not decided on apart from being non-standard as I don't have one with the engine. I do have access to a large no of mandrel bends though!
The car will be an 'BTDBTDBTDBTD special' as this is where the parts are coming from. So far I have an NOS Lola indycar rack, set of four WP dampers, bike engine...diff to come soon.

guilleracing
27-11-09, 20:33
Hi,

I have just upgraded from an RF 900 Suzuki engine to a K8 GSXR 1000 engine.

My carbs were rebuilt by an experienced drag race engine builder who put a dynojet kit in. The carbs were cleaned properly and put back together with the care of a watchmaker.

The result, two seasons of faultless running, no flat spots, no leaks in fact 100 per cent reliability.

So in answer to your question, Japanese motorcycle carbs are as reliable as you make them.

Greg.

Craig Powers
28-11-09, 13:57
Hi,

The carbs were cleaned properly ....

Greg.

That is good advice....

Anyone who has old bikes that stand with fuel in them for years will know of problems. I sold a 20 year old bike a while ago and the new owner solved the flat spot / misfire by ultrasonic cleaning of the carba.

If I was I any doubt about a set of carbs I would send them off for ultrasonic cleaning.

dennis.doyle
28-11-09, 15:12
Reckon it’s cheaper to have one of your own rather than sending carbs off. If you want an industrial quality one have a look at Sonicor (http://www.sonicor.com)



I had access to an SC-50-22 TH (big enough to get a ’45 in & with temperature controls) for 20 years:

Width: 13.5 cms
Length: 15 cms
Height: 10 cms
Capacity: 2 litres

It deteriorated but didn’t break down & the crud kept coming out of any carb put in it.

Finally, you could let your girlfriend/wife/lover clean their jewelry in it too - saving further money/strife/divorce.

guilleracing
28-11-09, 16:23
I think you buy small sonic cleaners on e-bay.

They are more of a size for the hobbist and not too expensive.

RaceMag
30-11-09, 00:05
Interesting information, thanks. I will find out about the Dynojet kits locally.

Fireblade
30-11-09, 09:40
Modern bike carbs have some very small holes and galleries internally which when blocked are a nightmare to clean. A combination of modern fuels and the manufacturing lacquers used by the Japs can lead to blocking especially when the carbs have stood for a while without having been drained. Honda Blackbird carbs are a classic for this. I have done a few of these for friends in the last couple of years.

I have witnessed the symptoms at a bike dealers where they haven't drained down a part exchange on a Saturday afternoon before putting it in the showroom. It gives the workshop a right headache when they eventually sell the bike 4 months later.
The only worst scenario is when a tank/carbs have been left with a 2 stroke pre mix in them and the oil settle around the bottom of the float, float needle jet and main jet.
Gloop is the only word for it.

Ultrasonics are a good way of cleaning carbs. Wash them down with petrol, blow off with air, stand to dry and put them in the cleaner.
However clean you think your carbs are the fluid in the cleaner tank will look positively scummy.

Craig Powers
30-11-09, 10:04
Modern bike carbs have some very small holes and galleries internally which when blocked are a nightmare to clean. A combination of modern fuels and the manufacturing lacquers used by the Japs can lead to blocking especially when the carbs have stood for a while without having been drained. Honda Blackbird carbs are a classic for this. I have done a few of these for friends in the last couple of years.

I have witnessed the symptoms at a bike dealers where they haven't drained down a part exchange on a Saturday afternoon before putting it in the showroom. It gives the workshop a right headache when they eventually sell the bike 4 months later.
The only worst scenario is when a tank/carbs have been left with a 2 stroke pre mix in them and the oil settle around the bottom of the float, float needle jet and main jet.
Gloop is the only word for it.

Ultrasonics are a good way of cleaning carbs. Wash them down with petrol, blow off with air, stand to dry and put them in the cleaner.
However clean you think your carbs are the fluid in the cleaner tank will look positively scummy.

I am very tempted to invest in an ultrasonic clearner. I have 3 sets of Keihin FCR flat slides plus 3 clasic bikes that stand for month / years without any action. Any recommendations on budget cleaners would be most welcome. I will check out the earlier recommendation for Sonicor.

Fireblade
30-11-09, 10:24
Ultrasonic cleaners, like most modern electrical, are attainable and affordable nowadays.
Even Maplins do a budget one, although I suggest you find something a little more robust. In years gone by I used to repair a fair amount for industrial customers.
Have never bothered with one of my own as within 3 miles of base camp there is a wealth of industrial degreasers, debburrers and specialist cleaners. I normally give the bits to a man in the pub to do for beer vouchers.

Craig Powers
30-11-09, 10:50
Ultrasonic cleaners, like most modern electrical, are attainable and affordable nowadays.
Even Maplins do a budget one, although I suggest you find something a little more robust. In years gone by I used to repair a fair amount for industrial customers.
Have never bothered with one of my own as within 3 miles of base camp there is a wealth of industrial degreasers, debburrers and specialist cleaners. I normally give the bits to a man in the pub to do for beer vouchers.


I think it will be worth it for me to buy one. I have heard quotes of 40 / carb and I don't know anyone who can do it as a back hander.

I have had a misfire at idle on a couple of pots this year and want to make sure that the FCR carbs are clean before I go to the rolling road early in 2010.

RaceMag
15-01-10, 04:35
I now have a set of 39mm FCR on the way. These were taken off a GSXR 750 of the same year as my engine - all hail BTDBTDBTDBTD I say! Anyway they will sit on the shelf as insurance and if are not needed will go back on BTDBTDBTDBTD.

Fireblade
15-01-10, 15:28
Further to comments re- Ultrasonic Cleaners. I notice an advert from ALDI in the dailies adverising a unit suitable for small parts. If I recall correctly it was 16.99

Hasta
15-01-10, 15:33
Further to comments re- Ultrasonic Cleaners. I notice an advert from ALDI in the dailies adverising a unit suitable for small parts. If I recall correctly it was 16.99

I hope you didn't pick up that flyer from the checkout :D:D


Hasta

Fireblade
15-01-10, 16:11
I hope you didn't pick up that flyer from the checkout :D:D


Hasta
Good lord no, perish the thought. It was in a newspaper not known for its appeal to the average ALDI shopper funnily enough.

redturner37
15-01-10, 18:29
Good lord no, perish the thought. It was in a newspaper not known for its appeal to the average ALDI shopper funnily enough. Surely, not the 'Motor Cycle News',

RaceMag
15-01-10, 23:32
so what is the stigma associated with Aldi in the UK?

dennis.doyle
16-01-10, 09:26
so what is the stigma associated with Aldi in the UK?

Good old-fashioned English class-consciousness I think the people who shop there look like they are poor & we are all frightened of catching it.

Actually you can get some good stuff there. I knew an IT manager who kitted us out with PCs from there & they worked fine. My only reservation is the cheap red wine. It costs tuppence (plus a couple of quid's worth of tax) & tastes like its worth thruppence.

RaceMag
17-01-10, 03:27
OK, makes some sense now. Last time I worked in the UK I was in Hull and frankly the local Aldi was the best choice we had other than driving 6 miles to Tesco. Aldi in Australia has a different profile, it's just another supermarket, albeit one that sells some strange stuff (e.g. wheelchairs!) at times.
Never tried the wine, we have bucket loads of cleanskin wines for 3-4 pounds per bottle at the local bottle shop for those that want it.

dennis.doyle
17-01-10, 10:25
Yes, they do have an interesting selection of “stuff”. The branch I sometimes go in often has tools, laser levellers, compressors, welding gear etc. I guess it isn’t in the “Snap-on” league & they may well include some plastic spanners judging from the prices. Still, it’s interesting to browse around. Anyone got any experiences of the quality of any of this? I guess I’d just like a bit of comfort in order to overcome my prejudices before opening wallet.

Fireblade
17-01-10, 10:56
You'll get a feel for what's not right Dennis.
I had a lad working for me to get some experience a couple of years back. He had an interesting assortment of tools some from Aldi/Lidl. Since I bent his bolster chisel into an 'S' shape whilst prising a board he has realised the importance of quality. :D

The odd bits aren't bad value. Alternator and cable testers for 3, Weather Station 9.99 but these items are electronic and a safer bet. General rule of thumb is if it needs to accurate and strong, jog on.

iranoff
17-01-10, 14:38
The sledgehammer and log-mauls are OK.

Beware any of their power-craft power tools. The starter dog on the petrol chainsaw lasts about 100 pulls. Not the bargain they seem. I have heard that the cheapo petrol gennies go the same way.

Stick with advice from the head gardener, steer clear of cheapo's and buy Stihl. He's a bit of a power tool snob, but he and his son give their Stihl kit the most exceptional stick and they keep coming back for more and service back up is excellent.

RaceMag
17-01-10, 22:36
I think the last thing I bought were a pack of jigsaw blades, which seem ok for the use and a laser level that I have not yet used.

Alpinepg
17-01-10, 22:41
Theres a creeping acceptance here that Aldi is ok....Ive bought their air tools before and found them to be well made and durable.
They have some excellent continental food as well and the drink aisle is fabulous compared to a similarly sized Tesco which will feature mostly lager and Chardonnay....Aldi have proper beer and some decent mid priced wines.
Particularly noteworthy is the cheese section which is bizarre but good!

redturner37
17-01-10, 23:23
Theres a creeping acceptance here that Aldi is ok....Ive bought their air tools before and found them to be well made and durable.
They have some excellent continental food as well and the drink aisle is fabulous compared to a similarly sized Tesco which will feature mostly lager and Chardonnay....Aldi have proper beer and some decent mid priced wines.
Particularly noteworthy is the cheese section which is bizarre but good!
I think a couple of our regular contributors have acquired a taste for their beer, :D..............

iranoff
17-01-10, 23:27
But Carslberg export 1 pint cans at 4 per 4 at Iceland is more persuasive.

RichardG
18-01-10, 00:04
Can't speak for Aldi but Lidl in Stourport do a quaffable South African Pinotage and the safety boots I bought from there have kept many heavy lumps of watermill off my toes.