Accepted wisdom for carb removal from 30 year inlets - 1100M

[Dezza]

It seems strange that carb rubbers to accommodate BST40s for the 1100 m/n models have gone up by nearly 100 quid relatively recently but those for the BST36s for the k/l models are still £160 a set (which is still expensive). The longer blandit 1200 rubbers for bst36s also now cost a fortune new (Going on Suzuki Performance Spares prices as I can't be arsed to trawl through parts fiches.)

[Joseph]

If you buy OE generic stuff from places like suzuki "performance" spares who mark stuff up liberally it's not going to be the cheapest route to take indeed.

They are still available each for 25-30€ VAT incl. for OE parts depending on which engine you are looking to equip.

[Dezza]

3 hours ago, Joseph said:

If you buy OE generic stuff from places like suzuki "performance" spares who mark stuff up liberally it's not going to be the cheapest route to take indeed.

They are still available each for 25-30€ VAT incl. for OE parts depending on which engine you are looking to equip.

Post link for where 1100 m/n new OEM rubbers are available at 30 euro to aid our OSS colleague

Edited September 2, 2021 by Dezza

[Joseph]

https://www.xexpress.fr/marque-suzuki.html

You need to open an account. Otherwise, a- you can't order. b- you don't see the discounted price.

Then, pick up the suzuki ref of each part you want, put it in the search engine, and add it to the basket.

You need to use this format (with the dash) otherwise it won't find the ref you put in :

so for the pipe order :

13101-40C00

13102-40C00

13103-40C00

13104-40C00

Total amount VAT included for real original Suzuki parts :

Just over £100 

It's a company based in the Netherlands so shipping is like flat rate 15€, but compared to the prices everyone on here is stating from "Suzuki friendly" shops in the UK it's worth it.

This website is a mild headache to use, and you need to edit the quantities you need once your basket is full of everything you want, it takes a while to complete an order 'cause you have to search and note down all the Suzuki part number from the fiches.

I buy all my spares from them when it comes to original parts, it all gets delivered with the real wrapping and suzuki sticker.

Worth the effort, but time is money.

i did a quote for all the bottom end bearings for a B12 2 days ago. The usual places it was around 375€, with these guys 250€... 

Sometimes there is backorder on parts, but they are reactive, let you know, and you always end up getting the stuff. If not, it's a no quibble refund

Edited September 2, 2021 by Joseph

[Nick]

Thanks Joseph/Dezza, that's great.

At £106 quid for a new set (1310#-41C00), it was a no brainer and I've ordered a set...

 

 

 

[Nick]

Bench tested as advised.  Glad I did, as the fuel t piece spigot seals pissed fuel out first go, though on inspection I'd pinched them putting the carbs back together.  

Now rigged it up again, and so far, so good.  Got the rubbers off with a PH3 JIS bit tapped into em and turned with a socket - thanks again.  Looked like they had threadlock on em - is this normal?!

[Gixer1460]

15 hours ago, Nick said:

  Looked like they had threadlock on em - is this normal?!

From the factory - yes! Its why they are so difficult to remove - soft non concrete thread locker can be used on reassembly but really not necessary!

[Nick]

So, progress has been slow, but I got the carbs back on after a successful bench test and it ran quite nicely on the stand in the garage, ticking over well and revving cleanly.

Bike is a stock 1127M with BST40's, and the airbox with a k&n panel and smallest aperture, and it has a full akra 4-1 with no baffle.

I opted for 140 mains, mixture screws at 2.5 turns out, standard pilots and needle position as standard (albeit offset to maintain the same protrusion as before as I am using Jonny1bump's spacers).

However, bike is now running crap again, dropping down onto 2 - 3 cylinders (2 seems to be the problem child).

I've looked at the ngk iridium plugs which are quite black and wet, indicating richness, and have checked that we have decent fat sparks and have trimmed the end off the HT leads, so I'm satisfied its a fuelling issue.

I've tried buggering about with the mixture screws (back to 2 turns as leaner - i think this is right as in turn out to richen? - but when I blip it, the engine revs then wants to die like it's running out of fuel) with no real joy.

So, when it ran beatifully, this was with a remote tank.  My 1100 tank is pristine and I flushed it and ran a magnet through it, but I wonder if there's a load of crap in the carbs again?

I didnt mess with the float levels when rebuilding them (as in bending the float 'tang').  My assumption is that the main jet wont affect idle as that is controlled by the pilot, so I'm not really sure where to go from here other than to pull the feckin things off and clean them again?

Fuel tap is one I rebuilt years ago as the one on the tank was wrecked from being stood and the seals had swollen.

Any ideas and thoughts gratefully received.  I know it'll need to go on a dyno to get properly set up, but it'd be nice to have it rideable to get there!

Thanks again...

 

[Gixer1460]

IMO i'd go back to stock or near stock settings ie. MJ @ 125 or maybe 127.5 (for the K&N and pipe) as I guess the majority richness is from the mid range ie. needles where overall fuelling is fed via the mains. Killing plugs with over fuelling is a money pit - I'd rather know its lean without killing plugs at £10 / hole and work from there or put sensible head on. pony up and stick it on a decent dyno with a load brake! 

PS - 40's are a royal PITA to get carbing right - just so you know LOL!

[Nick]

On 1/6/2022 at 11:35 AM, Gixer1460 said:

IMO i'd go back to stock or near stock settings ie. MJ @ 125 or maybe 127.5 (for the K&N and pipe) as I guess the majority richness is from the mid range ie. needles where overall fuelling is fed via the mains. Killing plugs with over fuelling is a money pit - I'd rather know its lean without killing plugs at £10 / hole and work from there or put sensible head on. pony up and stick it on a decent dyno with a load brake! 

PS - 40's are a royal PITA to get carbing right - just so you know LOL!

Thanks for this - pretty much exactly what I did.  Whipped them off again and swapped back to 125 MJ and treated them to some new brass mixture screws.

I've started off at 2 turns out, but noticed the revs would hang as they dropped from 'blipping it.'  As I've turned the screws out to richen it (no mean feat with the carbs still on the bike!), the hanging is less and less, so I reckon it was just leanness rather than an air leak?

Or am I way off the mark with this theory? Currently sat at about 2 and 5/8ths out...

Carb removal gets much quicker the more you do it, too.... !

[Gixer1460]

General wisdom for idle settings is, if screws are more than a turn to a turn & a quarter out from stock then a upsize on the idle jet is needed - yours still seems to be within the acceptable range. Garage tuning is ok up to a point, the engine really needs some load put on it to really see what its doing / needs - so its road time or dyno time!

[Upshotknothole]

Also I’ve had several old 750s with leaky boots and you have to drag the clutch when you stop to get the idle below 3K. Slight hang is most likely just jetting.