Topic: 76 CB550 hop up questions

[xedge4lifex]

I'm doing a very simple build for my summer engine, I just had some questions on performance upgrades. Obviously these are probably some of the simplest upgrades you can do and I would just like to bring the engine to life a little. I would just like to hear of everyone's experiences using one, two, all or any of the upgrades that i listed.

I've been reading on here that cb750 (early style) carbs will fit up to my engine. specifically what years would work without any or major modification. Also jetting and air filter advice

The cam from the early 80s 650 is also supposed to drop right in.

Exhaust via 4-1 4-2 or 4-4 free flowing but non obnoxious mufflers.

Ignition points vs electronic and "performance coils"

Weight reduction and where it can be most significant in pounds and also in handling

Any help is very appreciated
Thanks
Aaron

[Ecosse]

hi xedge4lifex and welcome to the forum. can i just call you xedge for short?  

btw: your post might be moved to another area as this spot is reserved i think for the serious boys and girls and their racers, but no worries.

i think the best place to start is to make sure your bike is tuned up, valves adjusted, carb sync, oil change, etc.. all the basics first. maybe a compression test too to make sure ya have a solid foundation.

i dunno but bigger carbs seem only necessary following serious head work and cam. although some folks have used later model carbs from other machines it seems like overkill unless the motor is really hopped up.

the 650 cam is a popular swap, and a dyna, or our friend hondaman's setup, are popular ignition upgrades.

if you are going through the motor many will point to the head (the bikes) as the source of untapped power. especially the 550 i think. so if you're rebuilding have mike ('rmieck') get into it. but now you're talking $$.

the only "low cost" exhaust (4-1) i know of is from mac but a few others (not many) offer a system too. price only goes up from mac tho. i think i remember a discussion about (stock 4-4) 750 exhausts and claims there wasn't much, if any, increase in hp with most aftermarket systems. that always intrigued me. safe to say a 4-1 would likely be lighter than stock anyway.

and don't forget the suspension!

check out faq, http://www.sohc4.net/index.php?q=content/tech-pages and http://www.sohc4.net/index.php?q=node/270

fwiw i think you might want to first form a clear idea of your expectations. do you want a solid everyday machine, a semi crazy cafe racer, track bike, etc...

i think many will agree a 550 sorted out and simply refurbished can be a lot of fun. unless of course you're spoiled by modern bikes and lots of hp.  



edit: out of curiosity i checked and you've been here since '09. so... a belated welcome anyway.  

[xedge4lifex]

hi xedge4lifex and welcome to the forum. can i just call you xedge for short? 

btw: your post might be moved to another area as this spot is reserved i think for the serious boys and girls and their racers, but no worries.

i think the best place to start is to make sure your bike is tuned up, valves adjusted, carb sync, oil change, etc.. all the basics first. maybe a compression test too to make sure ya have a solid foundation.

i dunno but bigger carbs seem only necessary following serious head work and cam. although some folks have used later model carbs from other machines it seems like overkill unless the motor is really hopped up.

the 650 cam is a popular swap, and a dyna, or our friend hondaman's setup, are popular ignition upgrades.

if you are going through the motor many will point to the head (the bikes) as the source of untapped power. especially the 550 i think. so if you're rebuilding have mike ('rmieck') get into it. but now you're talking $$.

the only "low cost" exhaust (4-1) i know of is from mac but a few others (not many) offer a system too. price only goes up from mac tho. i think i remember a discussion about (stock 4-4) 750 exhausts and claims there wasn't much, if any, increase in hp with most aftermarket systems. that always intrigued me. safe to say a 4-1 would likely be lighter than stock anyway.

and don't forget the suspension!

check out faq, http://www.sohc4.net/index.php?q=content/tech-pages and http://www.sohc4.net/index.php?q=node/270

fwiw i think you might want to first form a clear idea of your expectations. do you want a solid everyday machine, a semi crazy cafe racer, track bike, etc...

i think many will agree a 550 sorted out and simply refurbished can be a lot of fun. unless of course you're spoiled by modern bikes and lots of hp. 



edit: out of curiosity i checked and you've been here since '09. so... a belated welcome anyway. 

Thanks for all the advice!
As of last season the bike ran great, strong runner, carbs were sync'd, everything was in its place and working properly or as well as it could have been for a 35 year old 18k mile bike.

I probably will need bigger carbs as in the future they will be going on the labor of love engine im currently building. however as of right now the engine sits as stock, with decked head, valve job, and a very solid port and polish. The pipes that are on the bike are the original 4-2 with no baffles/rotted out mufflers.

the 650 cam as far as a power difference is it anything substantial? obviously 100 bones for an extra 5hp in a bike this size is worth it.

honestly its gotten to the point of; its the middle of summer my bike has been sitting while ive wrenched on what seems like everyones bike but mine. and after spending 20 hours on a built head id just like to see what other mods i could bolt up to give it some more guts while also getting it on the streets asap.

ill start posting more on the race engine im building soon, thanks again!
Aaron

[Ecosse]

sorry but typing w/ one hand eating with the other. no personal experience with 650 cam but everyone whose done it gives high marks.

my impression is the diff. is in power curves as much as peak hp. i say do it, especially with the head work you mentioned.