Topic: Wide tire application

[bobbed_750]

My question is about wide tire applications for a 1978 cb750. I have been reading all about cycle x's offset front and rear sprockets. some say this will work if you do this, this works if you do that but nobody really talks about what THEY have. These are the people I want to here from, specifically those running wide tires with the cycle x offset sprockets;
-WHAT TIRE ARE YOU RUNNING?
-WHAT WHEEL ARE YOU RUNNING?
-FRONT SPROCKET OFFSET?
-REAR SPROCKET OFFSET?
-COMPLETE BOLT ON OR MODIFICATION NEEDED?

I'm looking to run a 160-180 rear tire and just wanna hear from people who have done it.

[vanillagorilla]

Good question, looking forward to hearing the answer myself! 

[dusterdude]

im getting ready to put a cbr wheel with a 140 tire on my 750,it doesnt leave a lot of room for much else.

[Burnboy]

I have a 75 cb750. I put a 78 swing arm on it and got the front offset sprocket. I have a 160 tire on it. Its on a 16'' rim I believe 3.5 inches wide.

[bobbed_750]

I have a 75 cb750. I put a 78 swing arm on it and got the front offset sprocket. I have a 160 tire on it. Its on a 16'' rim I believe 3.5 inches wide.

Is that with a stock 75 cb750 wheel and rear sprocket?

[Burnboy]

harley rim wired to cb750 hub and stock sprocket

[SBKH]

Here's what I plan on running... dont know if it'll work yet but hopefully someone is running at least something comparable.

Aprilia SXV550 rear wheel. 17x6" with 18/55/17 tire. Gonna have to build a swing arm i think.

[KB02]

I've got a stock CB750K8 frame and swing arm. I am running an 160-60-17 rear tire with wheel off of a 1989 Suzuki Katana. I am NOT running offset sprockets.

I needed to make spacers to get the rear wheel centered and I had to have the sprocket carrier on the Kat wheel milled down to bring the sprocket in line with the stock front sprocket. It wasn't off by much.

You wouldn't want to go much wider than 160 with a stock swingarm.

[bobbed_750]

I guess I should have said from Jump street I dont have a swing arm.... I'm hard tail with an aman savior style frame.

[Retro Rocket]

CycleX have a 6inch rear rim and spokes for the 750 in a 16 inch rim..

Mick

[dusterdude]

I guess I should have said from Jump street I dont have a swing arm.... I'm hard tail with an aman savior style frame.

well hell,i reckon it depends on how much room have between the rails.it should be able to take a good sized tire.btw,rigids are cool.

[bobbed_750]

I know I got more than enough room to run a 180 rear tire frame wise just wasn't sure about hub, rear sprocket front sprocket alignment.

[Retro Rocket]

I am going torun a 180 on my 750 with  a swingarm though, it all just fits, i had to have a small amount machined off my alloy swingarm and i will use a 10mm {3/8} offset front sprocket, its very tight but it fits..

Mick

[mcuozzo]

Hey bobbed 750,

While I don't have a direct answer, I'll tell you who might.  Join and post over on www.hondachopper.com .   There are plenty of guys running hardtail amen frames over there.  Hopefully someone will have already put a 78 engine and sprockets on one.

I have a 78 engine but mine is going in a tigman frame.  I might be limited to a 160...

Good luck and be sure and post the answers/pictures...

Matt

[Retro Rocket]

Hmmmm, if i am correct the K8 output shaft sits further out than on the earlier K models, they have a wider rear rim as well and a wider rear sprocket carrier, so maybe no offset front needed.... Give Ken a call at Cycle x and ask him, he has been doing these conversions for years.
http://www.cyclexchange.net/Wheel%20Page.htm
http://www.cyclexchange.net/index%20pics/newest%20wheel%205.JPG
http://www.cyclexchange.net/index%20pics/big%20web%20rim.JPG

Mick

[bobbed_750]

I did a search over ther at hondachoppers and again everyone talks about it but it just seems like no one has followed through or if the had they didnt care to enlighten everyone lol. I will deff be taking some measure ments this weekend and figuring out what I need, just wanted to see if anyone could give me a jumpstart. How wide of a wheel do I need for a 160-180 tire im thinking 6 inches?

[Retro Rocket]

5-6 inch rim would suffice.  Most modern sportsbikes had the 5.5 inch rims on the rear for years and 180 fit no troubles.


Mick

[mcuozzo]

The problem is even though a tire is 180 (or 160) the widths still vary from manufacturer to manufacturer.  I usually try to check their websites for min/max rim recommendation.

Avon's for instance...http://forums.sohc4.net/index.php?action=post;topic=71866.0;num_replies=16

Post a question over on the chopper forum.  Maybe somebody has more up to date info...

And just keep an eye on ebay for wide rims if you need one.  They'll pop up cheaply ever once in a while.  I have one that I managed to get for $65.

Oooh, how wide can you go http://cgi.ebay.com/ebaymotors/Polished-Stainless-Steel-40-Spoke-7-x-16-Rim-NEW-/290362433238?cmd=ViewItem&pt=Motorcycles_Parts_Accessories&hash=item439af31ed6

[Ken41]

KB02,

How is the handling with your set up? Any wobbling noticed? I have a Katana rear wheel coming
and I have a CBR954RR front end to install. What did yo do for the rear brake? I most likely will not start on the change over until the weather turns in late fall, but I should have all the parts ready to go.

Ken