Sandman

This is not correct. All barrels for 1052 cc 1127 cc and 1157 cc have the same heigth. The length of the conrods for 1052 cc are 117.4 mm, and 1127 cc and 1157 cc are 117.0 mm. Therefore, the squish height for 1052 cc is 0.1 mm larger compared to the 1127 cc and 1157 cc engines (theoretlically) . The DOT head for GSXR 750 -88/89 are equal to the GSX750F. The difference is the camshafts. GSX750F has shorter duration and lower lift compared to GSXR 750. The DOT head comes with higher valve spring stiffness compared to the 1052 cc 1127 cc and 1157 cc engines. The rev limiter is higher for GSXR 750 -88/89 and GSX750F compared to 1052 cc, 1127 cc and 1157 cc engines. The valve stiffness for the DOT head is equal to the Yoshimura valve spring kit for ST-2 cams. The valve springs for the DOT head needs to be shimmed to get the correct seat pressure.

Same fittings on most of oil coolers for GSXR. The K5/K6 oil cooler has a triangular skape and fits well inside the fairing. It will not work together with Yoshimura headers. The oil cooler will interfere with front wheel.

This is the best option.

And the cover with the removable cover is heavier...

The 90/ 91 slingshot frame maybe taller than 88/89 frame. The longstroke engine is taller than the short stroke engine?

Thanks. These are not for sale .

Rocket science

Here is all you need: Valve seat cutter: : https://www.aliexpress.com/item/32798463004.html?spm=a2g0o.detail.1000060.2.72f23352iKUIqY&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.169870.0&scm_id=1007.13339.169870.0&scm-url=1007.13339.169870.0&pvid=9de12d2d-2235-46f0-8b8b-f38059d34e49&_t=gps-id:pcDetailBottomMoreThisSeller,scm-url:1007.13339.169870.0,pvid:9de12d2d-2235-46f0-8b8b-f38059d34e49,tpp_buckets:668%232846%238108%231977&&pdp_ext_f=%7B%22sceneId%22:%223339%22,%22sku_id%22:%2263964038181%22%7D some pilots: https://www.aliexpress.com/item/1005001692692343.html?spm=a2g0o.productlist.0.0.c47c49ceSSDKzt&algo_pvid=b3a6186d-15ca-4e0a-8e3d-62eeb2e532fe&algo_exp_id=b3a6186d-15ca-4e0a-8e3d-62eeb2e532fe-50&pdp_ext_f=%7B%22sku_id%22%3A%2212000017740129519%22%7D cutterblades from Goodson: https://goodson.com/collections/valve-seat-cutter-blades A powerfull elektromagnet and some cutting and welding. Maker sure the rig is very stiff. If the rig is to soft, the cutter starts to vibrate and the valve seats will look like shit. This is not rocket science.

That is correct. The jet needles can be changed by unlocking these top "screws".

Can anyone help me identify these carburetors? They have a inner diameter of 38 mm and the distance between the carburetors fits perfectly to GSXR 1100 -89.

Yes, just start cutting and welding. It is not rocket science.

Here is my homemade valve cutter for cutting seat for larger valves.

Why are you reducing the CR? In terms of its octane rating, ethanol has a rating of 113. Fuels with a higher octane rating reduce engine knocking and perform better. Also, almost all gasoline in the US contains 10 percent ethanol. When you mix 10 percent 113 octane ethanol with 85 octane gasoline it increases the octane two points to the normal 87 octane most consumers use. So the higher the ethanol content, the higher the octane. The octane rating for E15 (15% ethanol) is 88 octane and E85 (85% ethanol) is 108 octane. The use of ethanol blends in conventional gasoline vehicles is restricted to low mixtures, as ethanol is corrosive and can degrade some of the materials in the engine and fuel system. Also, the engine has to be adjusted for a higher compressive ratio as compared to a pure gasoline engine to take advantage of ethanol's higher oxygen content, thus allowing an improvement in fuel efficiency.