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Front end swap

Scorpion750

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Hello All, I just registered and new here. I'm hopeful I can get and share help. I just bought a cb750. According to the numbers the frame is a 76' and motor is 75'. Is this common? I had several bikes when I was younger when I had more money than brains now I have both. I plan to modify my 750 into my ideas of a cool bike. Before I take it apart I want to collect most of the parts. I've been researching front end swaps which is best ?. gsxr600/750 or 1000 or cbr750? I want duel disc. Out back, is the rear swing arm adequate or swap it out? What is a good replacement? I have a large home shop and I have above average fabrication skills. Thanks in advance. I'll post pictures on next posting.
 
After over 30 years its very common to have miss matched frame and engine. All the years of the sohc engines will swap so it was an easy fix when they had an issue just to swap engines.
 
Thank you for your reply. That makes sense. My pink slip and frame/engine numbers match. So I'm legit. Any ideas on which front end and or rear swing arm I should use? I'm actively looking at complete front ends with everything. GSXR 600 750 or 1000? Or CBR 750 or any ideas?đź’ˇ
 
Man, you are in no-mans' land now. Like asking what wings to put on my airplane after sawing the originals off. Simply way too much to process there, and it shows naivete on your part. It can be done but it's done by people who already have a rock solid idea of exactly what parts they'll use and rework. The front ends you mention are wildly un-bolt-on, it's like asking us to build your bike and by the way write a book on it. When you go that deep you are pretty much on your own with your own decision making calling the shots.

You need to do a LOT more research to get the well rounded thinking you'll need to do that. Like, forget how cool all the parts look and give serious consideration to measurements and sizes and things like that which are going to seriously impact your world if you are going to pull that off.

SOHC forks are 35 mm. IIRC, the others you mention are wildly bigger than that and you will be changing EVERYTHING and pretty much none of it simply bolts right up.

Not saying you can't do it at all, but you seriously need to open your eyes up to what will be going on there. There's literally 500 differences in any of those forks as compared to yours. Get out the tape measure and calipers, you are going to wear them out..................the people who do that stuff are walking numbers banks, they look at parts and see only numbers, how you work it all out. You can see the calculators going behind their eyes.
 
Thank you for your straight answer. I contacted a company called "Cognitomoto" and they have a cb750 frame conversion stem with the required bearings by "AllBalls Racing". This stem is supposed to work with 2006-2015 GSXR forks. It does require a press, (I have a 20 ton press). The guy I spoke too said a GSXR 600/750 front end will work. I have been doing inter web searching and this swap, seems more common than I thought. Apart from coolness I'm mostly want a better handling bike. IMG_5639.jpg. Now my question, has anyone done this swap? If so, how well does it work? Is there another option? As far as the stock swing arm it's plenty strong according to my recent searches, I came up with a "Dresada" as being top shelf without any benefits other than less weight. Anyway this is way too expensive over 1k. Once I remove the stock swing arm I'll look into welding some Gussets on the frame (I also tig/mig weld). I read that there is some flexing in the stock frame, any thoughts? I also plan to replace the bushings with Bronze. Any thoughts? I am a fabricator and not much is out of reach plus I also have this great resource in this Forum.
 
Link does not work but I need no education. I could do that type of stuff just my days of doing it are pretty much over.

The bronze bushings work well.

Frame mods are varied. You mean Dresda rather than Dresada on the arm.

I suggest you look up cb1100f.net and sign up for free, while it's the Honda early DOHC site, the bikes are similar in suspension and those forks do get bigger through later models. Also, some really far out front ends there to make you think. A lot of Honda CBR 600 stuff used from both front and rear.

Study up on what rake and trail do in terms of motorcycle handling, lots of food for thought there.
 
The link I sent was a breakdown of the front end parts offered by Cognintomoto. Spellcheck issues on "Dresda" glad you know what I'm talking about. Thanks for tip on Honda site. I'm for sure going to do my homework before I spend $$ & energy. Like I said before I just got the bike and am going to get parts before I take it apart. I want to build a great handling, updated cool to me bike. I am done working on my truck and needed a new project. Seems like you are very knowledgeable if I may ask what's you're background amc49?
 
LOL............large newspaper web off set printing press lead operator for 35 years. In that timespan I also worked at the family high-perf garage where we worked on all sorts of cars, mainly drag. We specialized in American Motors AMX drag cars, where we had them running in the mid 10s street legal cars using 395 cu.in. motors, our race car ran in the nines in the mid '70s. My younger brother campaigned a 700+ inch Camaro pro stocker in Texas heads up pro stock drag racing late '80s so got to work on several of those as well. Dad was a certified motorcycle nut and we had up to 20 bikes in the garage at one time in there somewhere too, I got to port both 2 and 4 stroke, mainly 2 and raced Yamaha twins and Kaw threes.

The garage was directly across the street from the local GM dealership and we could blow away anything that dealership put out including 454s coming out our ears. Eventually most of those guys wised up and brought their engines across the street for us to build.

LOTS of fun back then. You can't imagine how upset people can get when their super killer 454 Camaros get outrun and outpulled in HIGH gear by a much smaller 395 inch Rambler car.
 
I'm in the process of building a cafe racer from a 1978 Honda CBF 750...unfortunately I didn't pay much attention to the bearings that came out of the GSXR that I swapped with...is the conversion kit necessary or are their plans out their to fab your own?
 
I cant say for sure but I would bet you need a special set of bearings and probably a different shaft pressed in the gsxr triple clamps. I would start a new build thread on your bike, more people will look at the thread and possibly be able to give you more info.
 
Take a look at classified Moto, they use R6 mostly, it really depends on what you want for a look.. I built the walking dead bike clone but had to buy the upper triple and had those guys press in my stock (91 nighthawk) stem into the R6 lowers.. was going to stick a cbr600 front end on my 77 with a mono shock cb500x rear end but I like how clean the bike is so I'm going to use the hardware on another early nighthawk frame.. cognito is a good source.. I think the gsxr front ends are tapered slightly whereas the stock Honda stem is not.. you could buy cognitos stem though to press in or build up and machine down the stock Honda neck.. lots of options!
 
Hi Scorpion

I see this is a fairly old thread. Wondering how you're getting on with the GSXR fork swap as I started it myself and am finding all kinds of hurdles after simply getting the All Balls Racing conversion bearings. :/
 
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