Grove Posted July 25 Share Posted July 25 I need some help. Can’t decide if I’ve messed up or being thick. Ive got a 1100 oil cooled engine with a dot head (was this from a 750?) like it when I brought it. i have a set of carbs that won’t fit in the custom frame so went down the fuel injection route. I’ve got the large carb rubbers that fit the injection system, but when I put them on the engine they don’t line up with the injection system, same spacing as the carbs. do I need different rubbers or 750 carbs? it’s driving me mad Quote Link to comment
TonyGee Posted July 25 Share Posted July 25 have you got the rubbers in the right order ? their are 2 different types. Quote Link to comment
Dezza Posted July 25 Share Posted July 25 Is the injection set-up spaced correctly for an oil-cooled engine, the same as a set of carbs from an oil cooled bike (other than a Mk2 Blandit)? What bike are the rubbers from? Quote Link to comment
Grove Posted July 25 Author Share Posted July 25 7 minutes ago, TonyGee said: have you got the rubbers in the right order ? their are 2 different types. I’ve made sure I’ve got the up, up on them all. I have tried swapping them round and it made it even worse. Starting to wonder if the spacing is different on a 1100 head to a dot head. I’ve spent about 3 hours this afternoon just swooping and looking at them Quote Link to comment
Grove Posted July 25 Author Share Posted July 25 1 minute ago, Dezza said: Is the injection set-up spaced correctly for an oil-cooled engine, the same as a set of carbs from an oil cooled bike (other than a Mk2 Blandit)? What bike are the rubbers from? The injection was mounted on an oil cooled 1100 engine at Mk motorsport. The rubbers are supposed to be from a 1100 oil cooled. My carbs won’t line up with them either. I can line the two right one up then the two left ones don’t line up and vice versa Quote Link to comment
Upshotknothole Posted July 25 Share Posted July 25 Spacing is the same between 750 and 1100 heads. Only the 600s and Mk2 stuff from the 00s is different. Have the throttle bodies been modified to fit the spacing? I don't know of any that fit stock. The spacing between 1&2 and 3&4 look pretty far off in your photo. Quote Link to comment
Grove Posted July 25 Author Share Posted July 25 4 minutes ago, Upshotknothole said: Spacing is the same between 750 and 1100 heads. Only the 600s and Mk2 stuff from the 00s is different. Have the throttle bodies been modified to fit the spacing? I don't know of any that fit stock. The spacing between 1&2 and 3&4 look pretty far off in your photo. I can get either side to line up but not all 4 at once. They were mounted to an engine at mk motorsport and I got them and the carb rubbers from him. I have messaged mark and got to speak to him tomorrow. dont think the throttle bodies have been modified, its the same with the carbs Quote Link to comment
Upshotknothole Posted July 25 Share Posted July 25 Do you still have the carbs? Line the carbs and the throttle bodies up and see how they match up. 3 Quote Link to comment
george 1100 Posted July 25 Share Posted July 25 (edited) Check the part numbers on the rubbers. Should read ****1,****2,****3,****4 left to right. They may have done a mix and match,example 1144 Edited July 26 by george 1100 2 Quote Link to comment
Grove Posted July 26 Author Share Posted July 26 9 hours ago, Upshotknothole said: Do you still have the carbs? Line the carbs and the throttle bodies up and see how they match up. I’ve put the carbs against the throttle bodies and they line up. The carbs don’t line up with the rubbers either Quote Link to comment
Grove Posted July 26 Author Share Posted July 26 7 hours ago, george 1100 said: Check the part numbers on the rubbers. Should read ****1,****2,****3,****4 left to right. They may have done a mix and match,example 1144 Cheers mate. I’ll have a check when I get back from work Quote Link to comment
imago Posted July 26 Share Posted July 26 When I (and @davecara) fitted the 1250 bodies to oil cooled 1100s we used 4 rubbers that were either all outers, or all inners. Can't remember which unfortunately, but either way two are fitted the right way up, the other two the 'wrong' way. I think it was 2 & 3 upside down with 1 & 4 the right way up, but it's been a little while since I looked at it. The easiest approach to sorting it out is to slip the rubbers onto the TB stubs, then offer it up as a lump and rotate the rubbers to align with the bolt holes. 4 Quote Link to comment
davecara Posted July 26 Share Posted July 26 As @imagosaid, you'll need 2 sets of inlet rubbers and use both lots of outers or both lots of inner, both work but one positions the bodies lower. If you look at your TB's, theyre equally spaced, so if theyve come off an oil cooled motor theyve used a combination of inlet rubbers Quote Link to comment
bluedog59 Posted July 26 Share Posted July 26 MK Motorsport...........now where have I heard that name before ? Quote Link to comment
Upshotknothole Posted July 26 Share Posted July 26 If those are new intakes, the only place I know to easily pick up new intakes for a dot head is Eblag, and those ones are known to not work as they're not a full set. Instead they doubled up two of the intakes and called it good enough. Check the part numbers on them, correct ones are sequential left to right, the knock offs won't be. Quote Link to comment
GSX1100dreamn Posted July 26 Share Posted July 26 (edited) You did not say they were but, The throttle bodies do not look like 1250 throttle bodies ? Different TPS/ twin vacuum on #1 body/ different mounting screws for fuel rail/ injectors black (1250 green, 650 blue)/ center return spring arrangement and could be optical illusion but the spacing looks even ie 80/80/80. 1250 is 80/100/80. These below are 1250 throttle bodies. Edited July 26 by GSX1100dreamn added info 1 Quote Link to comment
Dezza Posted July 27 Share Posted July 27 What model bike(s) are the carbs and carb rubbers from? If both are from the same model bike then the carbs, and throttle bodies given they have the same spacings as the carbs, should fit. If you have a mix and match with either carbs or rubbers from a MK2 Blandit and carbs or rubbers from another oilcooled machine, then you'll get alignment problems. Quote Link to comment
Grove Posted July 27 Author Share Posted July 27 I’ve had a mate round tonight who builds race cars and plays with gsxr1000 throttle bodies on cars. Thinks that the number one rubber is wrong, said can put some spacers in the throttle bodies and make them work. So looking for a number one carb rubber if anyone has one for sale. Seems like the easiest way to go at the min, said that he would like to port the inlets too to get a better flow Quote Link to comment
Upshotknothole Posted July 27 Share Posted July 27 What are the part numbers on the inlets? There are quite a few different versions that all look pretty similar, but different lengths, different inlet sizes, and different spacing in the case of the MK2 stuff. Those ones you have look new, and if they're the chinese ones being sold on Eblag, they're known not to work because they're two pairs of the same intakes rather than 4 individual sizes. 1 Quote Link to comment
Grove Posted July 28 Author Share Posted July 28 2 minutes ago, Upshotknothole said: What are the part numbers on the inlets? There are quite a few different versions that all look pretty similar, but different lengths, different inlet sizes, and different spacing in the case of the MK2 stuff. Those ones you have look new, and if they're the chinese ones being sold on Eblag, they're known not to work because they're two pairs of the same intakes rather than 4 individual sizes. I’ll take a pic of them all tomorrow. I do have a random one with a pipe sticking out of it. I brought them from the same place I brought the frame, engine and throttle bodies from. He still owes me quite a few bits I’ve paid for but starting to get a bit pissed off with him. 1 Quote Link to comment
Upshotknothole Posted July 28 Share Posted July 28 (edited) 13 minutes ago, Grove said: I’ll take a pic of them all tomorrow. I do have a random one with a pipe sticking out of it. I brought them from the same place I brought the frame, engine and throttle bodies from. He still owes me quite a few bits I’ve paid for but starting to get a bit pissed off with him. Yeah, check the part numbers, they should all be the same except for one sequential number 1-4. That tube on the number 4 inlet is for the vacuum hose for the petcock. The thing that makes me question those so much is dot head intakes aren't made anymore, haven't been for a while, and there are a lot of us constantly searching for good used ones as they fit Mikuni RS carbs perfectly. So I think a lot of us are curious what the part numbers are on those and where they got them. I checked and the Chinese ones on Eblag don't have the vacuum tube, so no idea what yours are without the part numbers. Also, for in the future, the intake boot part numbers have 1-4 at the end of the first block of numbers, and that matches up with the cylinder they go on. Edited July 28 by Upshotknothole More info Quote Link to comment
Grove Posted July 28 Author Share Posted July 28 Just been in the workshop to have another play and take some photos of the inlet rubbers. I’ve split the throttle bodies and can get them to fit. I’ll get some spacers made up and just got to work out how to join the two opening parts together. The inlet rubbers don’t seem to line up perfectly with the inlets and could cause a bit of turbulence so might get them machined to match. Bit of progress I suppose. Quote Link to comment
BoostedRooster712 Posted July 29 Share Posted July 29 They're GSXR750RK rubbers. They're for 40mm carbs. Too big for my RS38s & 38mm CVs. Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.