Swirl Posted December 4, 2018 Share Posted December 4, 2018 I have picked up a U704 1052 slabby bottom end with a bit of research it seems it's from France and West Germany with a reduced power output, how would this be done carbs/exhaust is the bottom end the same as u703 Quote Link to comment
Gixer1460 Posted December 4, 2018 Share Posted December 4, 2018 22 minutes ago, Swirl said: I have picked up a U704 1052 slabby bottom end with a bit of research it seems it's from France and West Germany with a reduced power output, how would this be done carbs/exhaust is the bottom end the same as u703 Generally done with carbs and exhaust - easiest and cheapest. Sometimes via ignition. Nothing in the bottom end with ability to restrict output (without major cost) so should be identical! Quote Link to comment
Swirl Posted December 4, 2018 Author Share Posted December 4, 2018 2 minutes ago, Gixer1460 said: Generally done with carbs and exhaust - easiest and cheapest. Sometimes via ignition. Nothing in the bottom end with ability to restrict output (without major cost) so should be identical! What I was thinking Quote Link to comment
Blubber Posted December 4, 2018 Share Posted December 4, 2018 I know that the 1135 Ef was robbed of its power by the cams for some markets. I have seen carb tops with limited stop ( extra moulding) to reduce power. Most Japanese imports had a different CDI. Those 3 would be the items I would check on the parts site, to check were the difference between the country would be. Quote Link to comment
wsn03 Posted December 5, 2018 Share Posted December 5, 2018 20 hours ago, Blubber said: I know that the 1135 Ef was robbed of its power by the cams Most Japanese imports had a different CDI My 750F was from Japan. I have UK carbs...UK aftermarket exhaust. Are my cams and CDI likely to be different? Quote Link to comment
Blubber Posted December 5, 2018 Share Posted December 5, 2018 My bet would be just the CDI. Maybe @banoffeebanoffee can share his experience... If i am not mistaken 2 Quote Link to comment
banoffee Posted December 6, 2018 Share Posted December 6, 2018 My 750G slabby is indeed JDM. Made 101bhp on the dyno so isn’t restricted. I’ve replaced the exhaust, fitted k&n pods and rejetted. The CDI part number matches the UK one. So, either a previous owner fitted the CDI or the restriction was in the exhaust/jetting or it was never there. My old 750L was JDM too and was restricted. The CDI was different and had much smaller main jets. Easily sorted with a UK CDI and bigger mains. 1 Quote Link to comment
wsn03 Posted December 6, 2018 Share Posted December 6, 2018 (edited) 2 hours ago, banoffee said: My 750G slabby is indeed JDM. Made 101bhp on the dyno so isn’t restricted. I’ve replaced the exhaust, fitted k&n pods and rejetted. The CDI part number matches the UK one. So, either a previous owner fitted the CDI or the restriction was in the exhaust/jetting or it was never there. My old 750L was JDM too and was restricted. The CDI was different and had much smaller main jets. Easily sorted with a UK CDI and bigger mains. My 750F has 1100G carbs with I think a stage 1 dynojet kit fitted many years ago,(a mod I did with help from a guy who raced one at the TT with support from Dynojet), standard filter and a fairly standard road exhaust - it read I think 99 or 100 BHP on the last rolling road, so I presume it has a UK CDI - I will check though. Thanks Edited December 6, 2018 by wsn03 Quote Link to comment
billd Posted December 6, 2018 Share Posted December 6, 2018 What is the part number on your CDI please as I have an 85 GSXR750 that is an import and I would like to check it. I read some place that the only restrictions on the early GSXR's was an exhaust restrictor at the cylinder head area that was easily removed. Can someone confirm or comment on this please. Quote Link to comment
wsn03 Posted December 6, 2018 Share Posted December 6, 2018 8 hours ago, billd said: What is the part number on your CDI please as I have an 85 GSXR750 that is an import and I would like to check it. I read some place that the only restrictions on the early GSXR's was an exhaust restrictor at the cylinder head area that was easily removed. Can someone confirm or comment on this please. Ill get the CDI part number tomorrow...we have the same bike. I remember hearing the same as you and did find and bin the exhaust very restricted. Quote Link to comment
billd Posted December 6, 2018 Share Posted December 6, 2018 What was in the exhaust headers that acted as a restrict or that you removed? Look forward to getting the CDI part number, I will post mine here tomorrow as well. I've also just modified my accelerator pump Pistons to allow full stroke rather than just 1.5 mm as detailed under the post "Is my rod to long". It was suggested this also may have been a Japanese import method of restricting power but not confirmed. Quote Link to comment
billd Posted December 7, 2018 Share Posted December 7, 2018 (edited) My CDI part number is 32900-27AOO How does that compare to yours and more importantly how does it compare to a 198five UK market GSXR70F CDI #. If anyone one can respond it would be appreciated. The CDI unit also has a large "H" on its right hand side. Edited December 7, 2018 by billd wrong part # in original post Quote Link to comment
wsn03 Posted December 7, 2018 Share Posted December 7, 2018 1 hour ago, billd said: My CDI part number is 32900-27AOO How does that compare to yours and more importantly how does it compare to a 198five UK market GSXR70F CDI #. If anyone one can respond it would be appreciated. The CDI unit also has a large "H" on its right hand side. Quote Link to comment
wsn03 Posted December 7, 2018 Share Posted December 7, 2018 We have the same part number. Let me look it up on Fowlers Quote Link to comment
wsn03 Posted December 7, 2018 Share Posted December 7, 2018 Appears to be UK CDI Quote Link to comment
billd Posted December 7, 2018 Share Posted December 7, 2018 Bloody glad I don't need one!!! Quote Link to comment
wsn03 Posted December 7, 2018 Share Posted December 7, 2018 1 hour ago, billd said: Bloody glad I don't need one!!! Yeah same here!! Quote Link to comment
banoffee Posted December 7, 2018 Share Posted December 7, 2018 Just been out to the garage and popped the side panel off... mine is 131100-4641 too 1 Quote Link to comment
billd Posted December 7, 2018 Share Posted December 7, 2018 banoffee, what year is your bike please and is it a Japanese import or a UK market bike? Great having people around to learn from! Quote Link to comment
wsn03 Posted December 7, 2018 Share Posted December 7, 2018 (edited) On 12/6/2018 at 7:12 AM, banoffee said: My 750G slabby is indeed JDM. Made 101bhp on the dyno so isn’t restricted. I’ve replaced the exhaust, fitted k&n pods and rejetted. The CDI part number matches the UK one. So, either a previous owner fitted the CDI or the restriction was in the exhaust/jetting or it was never there. My old 750L was JDM too and was restricted. The CDI was different and had much smaller main jets. Easily sorted with a UK CDI and bigger mains. @billd My exhaust restriction btw was just in the size of the exhaust - I think it had like built restrictions that made the exhaust chambers very narrow, it was a case of just bin the whole system. It was 25 odd years ago so I don't remember very well Edited December 7, 2018 by wsn03 Quote Link to comment
Buzuki Posted December 7, 2018 Share Posted December 7, 2018 On 12/6/2018 at 2:22 PM, billd said: What is the part number on your CDI please as I have an 85 GSXR750 that is an import and I would like to check it. I read some place that the only restrictions on the early GSXR's was an exhaust restrictor at the cylinder head area that was easily removed. Can someone confirm or comment on this please. Also check for static compresion ratio ,first F model was with 9,8:1 but G/H models was with slightly higher 10,6:1 ratio . 1 Quote Link to comment
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