Topic: Performance Front end swap out?

[RainCityRider]

I have 3 1978 CB 750K's. I would like to modify one of them. I'm thinking replace the fork, F & R Brakes, and shocks for starters. Just looking for advice and guidance on what will fit and work best with minimal modifications.

[slikwilli420]

Sky is the limit. Gl1000 is a popular swap and is easy. Modern forks are another but require more work. You could go with some betor or ceriani forks if budget and skills allow. Any choice will give better brakes and handling. What goal ate you trying to accomplish?   

[SOHC4 Cafe Racer Fan]

Sky is the limit. Gl1000 is a popular swap and is easy. Modern forks are another but require more work. You could go with some betor or ceriani forks if budget and skills allow. Any choice will give better brakes and handling. What goal ate you trying to accomplish?

What slikwilli410 said.
If you want to stay period correct, swap in a 1975-1976 GL1000 entire front end (including brakes).  If period correctness is not a restriction, the sky is the limit with modern USD fork swaps and brakes.

[RainCityRider]

I want this bike to be a resto mod / performance cafe / rat bike. Open to making stuff work. But I'am not a moto mechanic. I have rebuilt one of my engines and done lots of moderate mechanical and cosmetic up grades. I'm a bicycle mechanic (25yrs) by trade so am mechanically inclined. I think a more modern front end with good brakes would be my preference. My other bikes are stockers, so I wanna play with this one a little.

[SOHC4 Cafe Racer Fan]

If it's going to be a resto-mod, then I would recommend a modern USD fork swap.  Buy an entire front from a mid-2000s GSXR (triple trees, forks, brakes, calipers, rotors, axle, and even the wheel if you like the forged style wheel).  You will only need to modify the steering stem -- press it out and press in a 750-length stem.  If you want spoke wheels, you can buy a new hub from Cognitomoto.com and relace to a rim and bolt on the modern rotors (the hubs are spaced to match the rotors).  You can buy a front end cheapest from a motorcycle wrecking yard, second cheapest from craigslist, third cheapest from ebay, and maybe somewhere in between there from the classifieds here.   

For instance, I am selling forks and brakes from a 2007 GSXR600 in the classifieds.

[Retro Rocket]

If you don't like the look of USD forks on these old bikes, there are some very good RSU {Right side up} alternatives, usually cheaper as well....

[SOHC4 Cafe Racer Fan]

Prior Gen Yamaha R6 front is a good conventional (non-USD) fork option.

[754]

If you go to USD... What do you plan for the back of the bike.?

[Retro Rocket]

Prior Gen Yamaha R6 front is a good conventional (non-USD) fork option.

Honda CBR 900 919, triumph triple 955 and 955 I and daytona up to 2004/5 use Showa RSU forks that are fully adjustable for rebound and damping in 43 and 45mm, the last model GSXR1100 with RSU forks was the 1989, 43mm , they are great forks, used a lot in classic racing, lots of adjustment, harder to get though. I just bought a complete set of the Triumph 955 I Showa forks with brakes and triples for $150 , an absolute bargain, great looking forks too...   I'll post pics if anyone is interested..

[RainCityRider]

@Retro Rocket I would love to see the pics!

For the rear end I think some piggy back shocks and a swing arm that will take discs would be sweet. But don't know if there are aftermarket swing arms?

Will the steer tube from the yamaha or the triumph swap over or do i need to get adapters or a different steer tube?

I found this for a gsxr swap.
https://cognitomoto.com/products/gsx-r-fork-on-honda-cb750-frame-conversion-stem?variant=512244181

[Retro Rocket]

@Retro Rocket I would love to see the pics!

For the rear end I think some piggy back shocks and a swing arm that will take discs would be sweet. But don't know if there are aftermarket swing arms?

Will the steer tube from the yamaha or the triumph swap over or do i need to get adapters or a different steer tube?

I found this for a gsxr swap.
https://cognitomoto.com/products/gsx-r-fork-on-honda-cb750-frame-conversion-stem?variant=512244181

There are lots of cheap Chinese piggy back shocks around, they are rubbish, there's been lots of threads about them here on the forum, they can be bought for as little as $16 dollars each direct from China...
Here's the triumph front end, very similar to the Ohlins RSU front ends... I paid $150 for all this, I'll remove the triumph from the calipers..

[Stev-o]

@Retro Rocket I would love to see the pics!

For the rear end I think some piggy back shocks and a swing arm that will take discs would be sweet. But don't know if there are aftermarket swing arms?

Will the steer tube from the yamaha or the triumph swap over or do i need to get adapters or a different steer tube?

I found this for a gsxr swap.
https://cognitomoto.com/products/gsx-r-fork-on-honda-cb750-frame-conversion-stem?variant=512244181

There are lots of cheap Chinese piggy back shocks around, they are rubbish, there's been lots of threads about them here on the forum, they can be bought for as little as $16 dollars each direct from China...
Here's the triumph front end, very similar to the Ohlins RSU front ends... I paid $150 for all this, I'll remove the triumph from the calipers..

How can you not be installing that??!!

[Retro Rocket]

@Retro Rocket I would love to see the pics!

For the rear end I think some piggy back shocks and a swing arm that will take discs would be sweet. But don't know if there are aftermarket swing arms?

Will the steer tube from the yamaha or the triumph swap over or do i need to get adapters or a different steer tube?

I found this for a gsxr swap.
https://cognitomoto.com/products/gsx-r-fork-on-honda-cb750-frame-conversion-stem?variant=512244181

There are lots of cheap Chinese piggy back shocks around, they are rubbish, there's been lots of threads about them here on the forum, they can be bought for as little as $16 dollars each direct from China...
Here's the triumph front end, very similar to the Ohlins RSU front ends... I paid $150 for all this, I'll remove the triumph from the calipers..

How can you not be installing that??!!

I will be Steve, they are for the 1000, by the way, these are showa forks, the same company Honda has used since the 60's.   

[RainCityRider]

Dang, Looks like a good deal. From what I have found. I need to find that kinda deal! Will the steer tube swap right over or will you need to mod it?

I don't want crap shocks. So I will look into what is a good set. Any idea if there is a way to put disc on the rear too?

[FunJimmy]

RainCity,

Check out my CB550 Interceptor build. I used Yamaha R6 RSU forks and Works Performance nitrogen charged piggy back shocks. I really good setup for a period correct resto-mod.

http://forums.sohc4.net/index.php/topic,27159.0.html

Coincidently, I'm selling the shocks if you're interested. They work flawlessly.
I'm going to shell out big for some Fox Podium RC1 shocks.

[Retro Rocket]

Dang, Looks like a good deal. From what I have found. I need to find that kinda deal! Will the steer tube swap right over or will you need to mod it?

I'm not using those clamps, I'm having custom clamps made to my specs with a new tube, I was only after the forks and brakes...

[754]

Jimmy, pm me price and length of the shocks..thanks..
 Retro,  Them Triumph forx look the business..

[seanbarney41]

Be aware that front end swaps are not usually a bolt on and go deal if you want to successfully improve the performance of your bike.  You will need to become very knowledgeable about motorcycle suspension and geometry and there will be necessary experimentation before you get it right.  I have found that improving stock components often yields better results faster...better oil, springs, fork braces, steering dampeners, cartridge emulators are all relatively easy improvements.

[Retro Rocket]

Be aware that front end swaps are not usually a bolt on and go deal if you want to successfully improve the performance of your bike.  You will need to become very knowledgeable about motorcycle suspension and geometry and there will be necessary experimentation before you get it right.  I have found that improving stock components often yields better results faster...better oil, springs, fork braces, steering dampeners, cartridge emulators are all relatively easy improvements.

Agreed, I wasn't wanting to go into that here, there's plenty of other threads that cover that..

Retro,  Them Triumph forx look the business..

They do indeed Frank, same forks used on the Honda Fireblades of the late 90's, early 2000's, I'll stick some racetech valves in them and they'll be as good as the exorbitantly expensive Ohlins...

[FunJimmy]

They do indeed Frank, same forks used on the Honda Fireblades of the late 90's, early 2000's, I'll stick some racetech valves in them and they'll be as good as the exorbitantly expensive Ohlins...

No they won't but you can keep telling yourself that.

[FunJimmy]

BTW, always check overall fork length.
A lot of sport bikes have forks much shorter than your stock forks. Try to find forks of similar length.

[Retro Rocket]

BTW, always check overall fork length.
A lot of sport bikes have forks much shorter than your stock forks. Try to find forks of similar length.

That can be dealt with quite easily, I've had spacers made that screwed straight into the top of the fork, relatively easy to have done, you can either paint the extension or have it hard chromed. I'd rather go for a quality fork/disk/wheel or what ever, and make it fit, for a "straight" conversion length and offset should both be addressed... Also, using original size wheels and tires, instead of modern 17's, adds more height to the front end..

[FunJimmy]

BTW, always check overall fork length.
A lot of sport bikes have forks much shorter than your stock forks. Try to find forks of similar length.

That can be dealt with quite easily, I've had spacers made that screwed straight into the top of the fork, relatively easy to have done, you can either paint the extension or have it hard chromed. I'd rather go for a quality fork/disk/wheel or what ever, and make it fit, for a "straight" conversion length and offset should both be addressed... Also, using original size wheels and tires, instead of modern 17's, adds more height to the front end..

Are these what you're refering to Mick? Not sure who made them or if they're commercially available for a wide variety of forks but it sure would solve the length issue.

[Retro Rocket]

BTW, always check overall fork length.
A lot of sport bikes have forks much shorter than your stock forks. Try to find forks of similar length.

That can be dealt with quite easily, I've had spacers made that screwed straight into the top of the fork, relatively easy to have done, you can either paint the extension or have it hard chromed. I'd rather go for a quality fork/disk/wheel or what ever, and make it fit, for a "straight" conversion length and offset should both be addressed... Also, using original size wheels and tires, instead of modern 17's, adds more height to the front end..

Are these what you're refering to Mick? Not sure who made them or if they're commercially available for a wide variety of forks but it sure would solve the length issue.

Very similar, I had an engineer friend thread some steel tube {same ID and OD as the forks} both top and bottom so I could just screw it on and fit the stock preload adjusters to the top, all I needed was a similar sized spacer internally so the preload adjuster worked as intended, if I had a lathe I could have made it myself, a good friend just bought a big lathe so that should make things easier in the future...

Like this..

[FunJimmy]

Very similar, I had an engineer friend thread some steel tube {same ID and OD as the forks} both top and bottom so I could just screw it on and fit the stock preload adjusters to the top, all I needed was a similar sized spacer internally so the preload adjuster worked as intended, if I had a lathe I could have made it myself, a good friend just bought a big lathe so that should make things easier in the future...

Like this..

That's a much nicer solution. Stealthy.
The one I found looks odd with the preload adjuster sunk so deeply.