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1981 750C build

Hillbilly Bike

CB750 Member
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Western NY
I bought this 750C 6 months ago and over the winter I modified in to what you see here..Cut off unneeded brackets....96 VRF750 front forks, 93 VRF 17 inch front wheel with larger 96 brake discs and calipers...late 80's VRF rear wheel and disc brake. 71 Triumph 650 rear fender..Yamaha XS750 gas tank...90 Sportster solo seat...Home made rear set pegs and controls. Needed to spread the rear swing arm to get the rear wheel where it belonged.A late 80's 20 MM speedo drive is on the rear axle, no room on the from to install it...I pressed out the 750C steering stem and used it for the 96 VRF front forks. As it sits , 26 degrees rake and 4.2 inches of trail .I removed the engine to replace the gaskets, new rings and valve guide seals...Dyno Jet kit to deal with the pods..A few more minor things to clean up...It's not everyone's style but I like it...

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I've been riding the bike ...At first the carbs were impossible to synchronize.The rubber intake boots were leaking...new boots and clamps...What a difference....The Dynojet kit, stage 3 with their needle ,the clip second notch from the bottom, works nicely with the oval pods and the exhaust system...Decent low rpm power with a nice rush from 6500- 9500....Or so because the tach is a bit erratic. With the 96 VRF front forks and wheel, 89 VRF rear wheel the bike is steady in the turns but something is weird feeling so I won't push it...I believe it's the Avon Road Rider tires....I know another guy who says they feel greasy...
 
Where did you find the front end?
EBAY, it was 120 bucks to my door...I also got both wheels, brake parts, handlebars , risers, muffler,seat and the battery from Ebay.Air filters and a few misc. parts from 4 into 1..The tires from American Motorcycle tires, the rest from Amazon....An internet built bike...
 
How was the installation? Did you document any of these mods? This is potentially what I want to do with mine. Slowly upgrade the front end. But I don't know what will plug and play.
 
Would a Stock 41mm Showa forks off a 1996 VFR 750 fit (with triple trees)?

Unfortunately I lost the many of the build photos when my computer blew up.I have done two other Showa fork swaps from Suzukis on vintahe Triumphs..Ok the stock 96 VFR 750 front end sorta bolted onto the 81 750...My 81 is a C model ,I believe there's some slight frame differences compared to a K or F . .If all the frame steering necks are the same height it goes like this..The 81 and 96 tree stems are different heights. I removed the steering neck from the stock 81 C lower tree (yoke) by grinding off the weld on the bottom. The stem will then press out..or drift out with a hammer. Did the same for the 96 750 VRF tree.. Then pressed in the 81 stem and welded the bottom like stock..The bearings are the same for both....The VFR tress have less offset than the stock C trees...Actually the C trees are raked....Less offset can slow up the steering a bit...So I adjusted the ride height so the front forks have a 26 degree rake....You may not have to do this depending on how you like the bike to steer..The front wheel is a 93 using 96 and newer VFR disc and calipers...I like the beefier look of the 41mm tubes and big brake discs..
The 96 front end has no speedo drive.....I bought an 80's VFR front speedo drive because it's 20 mm like the rear axle....I fitted the speedo to the rear axle using home made spacers .. The 89 VFR 18 x 3.5 rear wheel actually fit, the sprocket lined up with the trans sprocket while the center of the rim was inline with the front wheel...But..I had to spread the swingarm wider buy 3/4 inch. Easily done with a hydraulic ram.....Then I bought cable for the 80's VFR... I spliced the new cable to the original 81 C front cable with a short length of crimped brake line tubing and the whole cable came out the perfect length ..and...The damn speedo is accurate... very lucky because I was just guessing..

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This one photo shows the bike on work table with levels and angle finder setting up the steering geometry

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Thanks, if you have any more question do ask...I don't keep track of stuff on paper so I forget some of it.You can email me .. Front ends swaps are not that difficult and the rewards can be well worth it..
 
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