I think my 77 GS750 has a Wiseco 844 kit in it already (it's fast as hell, previous owner said "guy I got it from said the moter's been boared"), and it seems to run fine without an oil cooler. I am going to probably upgrade to 850 cylinder jugs and MTC Engineering 10:1 920cc 72mm pistons (3mm over for the 850 jugs, 1.5mm less cylinder wall thickness). I was worried about engine temps running hard in the summer, and fighting off detonation. I got the pistons and jugs before I really had ridden the bike much, and after putting it through the paces in the southern Ohio hills and national forests several times against my buddy's 1132cc KZ1000, I realized that the bike is really darn fast as is, but I have a weeping oil seep out of the cam chain tunnel area, so I need to yank it apart anyway, and I can get rid of the suspect cam chain tunnel o-ring if I go with the 73mm bore MLS (multi-layer steel) newer GS1100 head gasket that I would need anyway with the 72mm pistons. So I will still probably be swapping out to 920cc for the uniqueness (out of production NOS MTC Engineering pistons!), as much as the performance gains.
Most on this board have told me that unless riding hard in intense summer heat, an oil cooler is not needed, but I am still worried. I was wondering how anyone has hooked up engine or oil temperature gauges to our bikes, also wondered if there is a combination oil temp/pressure gauge out there?
I don't have an exhaust gas analyzer to tell me if I have my carbs tuned properly, but I think it was 49er on here that has an 894cc 850 and he was giving me great updates on dyno tuning his 850 based big bore experiments using a dyno and probably exhaust gas analyzer to tune. Sounds like I will need smaller jets than planned, but I don't want to go too lean, as lean runs hot!
I figured I will take my ugly rusty black MAC headers and modify them a bit, recoat them, and wrap them with exhaust insulation wrap to combat any extra hot air hampering the engine's cooling. Also, making sure my timing is not too advanced, and tuning the carbs to 49er's findings on his engines and maybe going up one jet size beyond. Going to look for some Rotella synthetic diesel oil as well, as synthetic doesn't break down in high temps like conventional oil does, and the good diesel oils have all the great additives without the extra high cost of motorcycle specific oil.
Being in the capital of Ohio, Columbus, there are several dynos around town that I could probably utilize for a price if I was really worried about dialing it in perfect. I was wondering if going with big bore kits and running hot was more of an effect of the higher compression ratios, or due to the cylinder walls being thinner, or both? MTC actually shaved down my pistons to go from 10.5:1 to just a hair under 10:1 due to my street riding and concerns.
Most on this board have told me that unless riding hard in intense summer heat, an oil cooler is not needed, but I am still worried. I was wondering how anyone has hooked up engine or oil temperature gauges to our bikes, also wondered if there is a combination oil temp/pressure gauge out there?
I don't have an exhaust gas analyzer to tell me if I have my carbs tuned properly, but I think it was 49er on here that has an 894cc 850 and he was giving me great updates on dyno tuning his 850 based big bore experiments using a dyno and probably exhaust gas analyzer to tune. Sounds like I will need smaller jets than planned, but I don't want to go too lean, as lean runs hot!
I figured I will take my ugly rusty black MAC headers and modify them a bit, recoat them, and wrap them with exhaust insulation wrap to combat any extra hot air hampering the engine's cooling. Also, making sure my timing is not too advanced, and tuning the carbs to 49er's findings on his engines and maybe going up one jet size beyond. Going to look for some Rotella synthetic diesel oil as well, as synthetic doesn't break down in high temps like conventional oil does, and the good diesel oils have all the great additives without the extra high cost of motorcycle specific oil.
Being in the capital of Ohio, Columbus, there are several dynos around town that I could probably utilize for a price if I was really worried about dialing it in perfect. I was wondering if going with big bore kits and running hot was more of an effect of the higher compression ratios, or due to the cylinder walls being thinner, or both? MTC actually shaved down my pistons to go from 10.5:1 to just a hair under 10:1 due to my street riding and concerns.
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