kev34 Posted December 18, 2019 Posted December 18, 2019 Really good info here, great to see these pics to understand sizes
Dezza Posted March 12, 2020 Author Posted March 12, 2020 (edited) Picture update showing the misalignment of a carb rubber and inlet port. The carb rubbers are the wopping great ones from a GSXR 750L that accommodate 38mm BSTs and RS 34,36 or 38s, which have an id of 42mm. The head is a Blandit 1200 mk1. Also, I have noticed that the o'rings in these larger rubbers have a larger id (~42mm) than those from the Blandit (~40mm) so check first before ordering new o'rings from Suzuki. Edited March 12, 2020 by Dezza
fab Posted March 13, 2020 Posted March 13, 2020 awesome right up fellas, really good info thanks heaps.
gsxr1385 Posted March 26, 2020 Posted March 26, 2020 Great thread glad I found it … wish I had it years ago when trying to fit carbs to my bikes! I thought I would add some information to this thread that I have uncovered in my trials and tribulations and may cause some wringing of hands as it conflicts with some of the info I read in this topic. The following is based on equipment that I have in my hands and measured for myself, and also cross referenced with the Suzuki part numbers on the inlet rubbers. - Carb spacing for the USA model GSXR 1100 K and L models is 78-90-78. Both measured on the stock rubbers mounted on the engine and the stock BST 36 carbs. - Carb spacing for a FCR 39 and 41 for the air-cooled GSXR 750 (and 1100) carbs measure 78-89-78. One of the biggest FCR suppliers in the USA (Bolt on Performance) confirms these dimensions. - Carb spacing of a set of Mikuni RS40 I took off a 90 GSXR 1100 is 78-93-78 - Carb spacing for a set of FCR 39 I was told came from a 93-98 water cooled GSXR 1100 was 86-92-86. Again I was told these came from that bike, I cannot confirm that. - FCR carb outlet spigots are NOT one size; various sizes can be purchased to fit different inlet rubbers (They screw in). - With that said, an FCR 41 spigot part number 869 will fit in the stock GSXR 1100 K&L rubbers (USA models) - FCR 39 spigot 21C fits into the GSXR 750 L&M rubbers (meant for the BST 38). - Per Keihin's spigot dimension and cross reference charts, the FCR 41 spigot 33B should also fit in these GSXR 750 L&M rubbers (I hope so as I am buying these for my setup). 3
Goo'Roo Posted April 10, 2020 Posted April 10, 2020 Left: Gsx 1100 F short angled down few degrees Center: Gsx 750 F MK1 dot short straight Right: Gsf1200 MK1 long straight 1
yann7/11r Posted April 13, 2020 Posted April 13, 2020 Some years ago (2012) on my MotoMartin, i've mounted some W 38bst carbs. 1127cc Engine from 1990. Rubber ref : -Cyl N°1 41C0 13120-Cyl N°2 41C0 13120-Cyl N°3 41C0 13130-Cyl N°4 41C0 13130
Dezza Posted April 13, 2020 Author Posted April 13, 2020 39 minutes ago, yann7/11r said: Some years ago (2012) on my MotoMartin, i've mounted some W 38bst carbs. 1127cc Engine from 1990. Rubber ref : -Cyl N°1 41C0 13120-Cyl N°2 41C0 13120-Cyl N°3 41C0 13130-Cyl N°4 41C0 13130 Interesting: what model are these rubbers originally from?
yann7/11r Posted April 14, 2020 Posted April 14, 2020 At the time, i was able to buy a basket case bike. Looked as a 1100 M. Previous owner had buy bargain spare parts to fix it. (you may say this is not a good point for the infos...) I didn't repair it, but used miscellianous parts for my others bikes. Concerning the rubber (after measurment ) my conclusion for the rubber was that they came from a GsxR 1100 92. (aka 40mm carbs) I finded other rubber in a autojumble with the same size (40mm carbs) When i've done the montage i used the rubber in this order: Rubber réf. : -Cyl N ° 1 41C0 13120 -Cyl N ° 2 41C0 13120 -Cyl N ° 3 41C0 13130 -Cyl N ° 4 41C0 13130 What i've noted in my personnal note at the time: Which (in CLEAR) corresponds: - to use rubber N ° 2 on cylinders N ° 1 and 2 - to use rubber N ° 3 on cylinders N ° 3 and 4 It is therefore necessary to have 2 sets of rubber for 40mm carbs to carry out the assembly of W carbs on an -oil cooled engine. As you precised before Dezza, some misallignement are notable with the inlet port. Was thinked doing some retouche but never did it. Carbs are still on my MotoMartin and works great in term of perfo. 1
Dezza Posted April 14, 2020 Author Posted April 14, 2020 (edited) Ok, I understand now: to mount BST 38s from a 750W to an oilcooled head you used the (huge) rubbers from an 1100 M, but needed 2 sets of the inner rubbers (2 X 3 & 4) to do so rather than a single set of rubbers 1-4 Edited April 14, 2020 by Dezza
yann7/11r Posted April 14, 2020 Posted April 14, 2020 11 minutes ago, Dezza said: Ok, I understand now: to mount BST 38s from a 750W to an oilcooled head you used the (huge) rubbers from an 1100 M, but needed 2 sets of the inner rubbers (2 X 3 & 4) to do so rather than a single set of rubbers 1-4 @Dezza No. You need : 2x inner rubbers N°2 (13120) 2x inner rubbers N°3 (13130) 1
Dezza Posted April 14, 2020 Author Posted April 14, 2020 3 hours ago, yann7/11r said: @Dezza No. You need : 2x inner rubbers N°2 (13120) 2x inner rubbers N°3 (13130) Typo: I wrote 4 instead of 2, doh!
Askamaskinservice Posted April 15, 2020 Posted April 15, 2020 Look here :https://oldskoolsuzuki.info/forums/topic/8818-inlet-rubbers/
Otatts Posted April 25, 2020 Posted April 25, 2020 1 hour ago, Otatts said: For anyone wondering about height differences between RS and CV these are some 38mm back to back. Measures about a 7-10mm difference. (He put a tape measure up to them but was kinda hard to make out in the pics) Hopefully this is what you meant @Dezza still learning my way around the site. Wish I had of found this thread earlier. Great work guys
Dezza Posted April 25, 2020 Author Posted April 25, 2020 (edited) 42 minutes ago, Otatts said: Hopefully this is what you meant @Dezza still learning my way around the site. Wish I had of found this thread earlier. Great work guys Yes, thanks. This picture shows the overall height difference between BST38mm carbs (GSXR 750 L,M) and RS Mikuni flatslides. As is clear, the BST 38s are pretty tall so may cause clearance problems depending on the application, especially when using a 750 DOT head that has slightly higher-angled inlets compared with other oil-cooled heads. Edited April 25, 2020 by Dezza
Otatts Posted April 25, 2020 Posted April 25, 2020 Also something else I’d noticed while messing about with multiple carbs trying to solve a vacuum leak is that the carb caps are different heights on the slingshot 750 36bst (left) and mk1 bandit12 36bst’s (right). 25mm for the 750 and 30mm for the bandit. I noticed a couple guys using bandit carbs for the DOT/B12 in 750 frame builds with super tight fits so this might help get a few more mm clearance 2
Peterbertie Posted July 11, 2020 Posted July 11, 2020 Hello folks a newbie in need I have been trawling through the interchangable carb thread and fried my brain I have a 750 inazuma with a butchered float valve seat and believe they are not repairable so I'm looking for the easiest option to solve my problems Many thanks So I've seen the gsf 600 2000 to 2004 carbs on inlet and air box are exactly the same size also measure from front to back the same, has any one fitted these to the 750 Zuma ? Before I go and waste wages on a set ?
Dezza Posted July 11, 2020 Author Posted July 11, 2020 (edited) I would suggest a set of Blandit 1200 BST36s with the corresponding carb rubbers, as these are freely available and relatively cheap. If you need more space between the back of the carbs and the airbox, then try and source a set of GSXR 750 j,k rubbers as these bring the carbs 5mm closer to the head. What you have to do to them to get the engine to run well I have no idea but when set up correctly with a decent pipe my guess is you'd get a pretty good power increase Edited July 11, 2020 by Dezza
Peterbertie Posted July 11, 2020 Posted July 11, 2020 22 minutes ago, Dezza said: I would suggest a set of Blandit 1200 BST36s with the corresponding carb rubbers, as these are freely available and relatively cheap. If you need more space between the back of the carbs and the airbox, then try and source a set of GSXR 750 j,k rubbers as these bring the carbs 5mm closer to the head. What you have to do to them to get the engine to run well I have no idea but when set up correctly with a decent pipe my guess is you'd get a pretty good power increase Ok I will look for them someone on here will undoubtedly know what's needed to set them up and I'm already fitted with a nice Yoshi pipe
Besty188 Posted September 21, 2020 Posted September 21, 2020 I have an 1100WP that's going into my race sidecar, anyone know the spacing for the 1100WP? Is it still 77-93-77?
Dezza Posted September 21, 2020 Author Posted September 21, 2020 21 minutes ago, Besty188 said: I have an 1100WP that's going into my race sidecar, anyone know the spacing for the 1100WP? Is it still 77-93-77? No, they are the same as the WC 1st generation 750s: 85-90-85. For a first post, do an intro and post a pic of your bike. Otherwise you'll get a bollocking from 'The Management.'
Besty188 Posted September 21, 2020 Posted September 21, 2020 Thanks for the tip Dezza, noted and thanks for the info on the spacing. I'd post a pic of the bike but it's a F2 race sidecar with a 750 K9 in there just now, the WP is a Winter Project in preparation for next Season's FSRA Pre-injection Series. I'll post a pic when it's done and ready to go though
nono Posted November 23, 2020 Posted November 23, 2020 I learned something today, even though the old 750-1000 air cooled Kawasakis are close to the same spacing as the Suzuki they're a little different. Kawasaki is 75-96-75 when you line up the 2 intake to intake you can see the difference. But the Kawasaki's will work on the Suzuki's with a persuasion.
TonyGee Posted November 23, 2020 Posted November 23, 2020 you might be able to clear up a mystery for me here ? i was messing about with an inazuma frame/project, i was gona use a b12 engine but i only had a set of b600 carbs i was gona use till i got a set of b12 carbs. the 32mm b6 carbs and rubbers went on no problem ( i know the 1200 zuma uses 32mm carbs as does the 1200ss ) but when i opened the throttle it moved just a few mm ? the middle balance adjuster touches the cam chain tunnel on the head. when i looked up zuma carbs they where the same !! i checked the zuma rubbers part number and they where just for that model, so my guess is are the rubbers longer than the 600 so the adjuster will clear ? i couldn't get hold of a set to measure to confirm !!!!
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