Beach cruiser build

WideAWAKE

Single Fins and Twin Cylinders
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Ok so here goes it...

I figure I’ll document this all in one place because I’m still in a bit of the planning stage but thus far it looks like this.

physically I am planning to build a bike based off the triumph Tr6 trophy to putt along the beach/dunes and back roads.

the physical build, to me, is the easy part but the motor I got a few questions about.

I’ve owned 3 of these bikes in the past, all pretty much stock and original and ran like champs so motor work never needed to be done.

I’ve rebuilt several motors but was hoping for some insight from those far more knowledgeable than I on this one.

my loose plan for the motor thus far...

I have an 81 special that I have yet to crack open but what I do know is that it turns freely , shifts easily and has good compression.

I am planning to put a 750BBK on it but keep it pretty mild beyond that. This isn’t a screamer and will not likely be ridden too hard.

I’ve got a set of mikuni VM34s that were from an xs650 “kit” but I have yet to confirm any of the jetting (which I know I will need to fuss with I’m sure)

I’ve got some real nice high pipes on the way (curtesy of DogBunny) and some torque cones on order as well.

as for the rest of the motor my plan was to keep it pretty much stock beyond that. But I do have some questions/concerns about the clutch and valve set up.

What are the thoughts/opinions of running stock valves/ guides/ springs (granted they spec out fine) would a HD set of springs do much for me here granted the cam and valves are stock??

and with the clutch - the thought was run some HD vesrah springs and Barnett friction plates and see how she does.

Sooo any glaringly obvious no-no’s here??

the motor is gonna be pulled all apart and obviously I’ll check all the bearings and crank but I’m lookin for some planning guidance here.

I am in the midst of amassing parts but should be getting started with the physical build part of the equation pretty soon.

any help is greatly appreciated!!

*edit - I will be running a boyers ignition (blue) as well.
 
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You`ve already got the 750 kit, exhaust and 34mm Mikuni`s so you might as well go ahead and put a good cam and valve train in it. It`s better to do it now than get it all together and later wish you did. :thumbsup:
 
What are the thoughts/opinions of running stock valves/ guides/ springs (granted they spec out fine) would a HD set of springs do much for me here granted the cam and valves are stock??
If you're staying with the stock cam, I'd stay stock with the rest of the valvetrain as well. Really no point in changing it. Maybe clean up the roughness in the ports, but that's all I'd do if I'm keeping the stock cam.
 
You`ve already got the 750 kit, exhaust and 34mm Mikuni`s so you might as well go ahead and put a good cam and valve train in it. It`s better to do it now than get it all together and later wish you did. :thumbsup:


Well because the goal is more of a “super stock” not a racer and well doin it your way is a decent bit of extra coin haha.

BUT I haven’t cracked the motor open yet so depending on how the valve train looks, if things need replacing and real work needs to be done then upgrades may not be too much of an added cost.
 
If you're staying with the stock cam, I'd stay stock with the rest of the valvetrain as well. Really no point in changing it. Maybe clean up the roughness in the ports, but that's all I'd do if I'm keeping the stock cam.

I much appreciate the input.

Smoothing out the ports is on my list of standard things to do when the head is off.
 
Wow, Nice to log on and see this kind of action !
What style is a "Beach Cruiser"? As in looking like a beach cruiser or to be used cruisin the beach roads? What frame and wheels do you have in mind to build on?
Sounds real fun to watch!
Good luck -R
 
Wow, Nice to log on and see this kind of action !
What style is a "Beach Cruiser"? As in looking like a beach cruiser or to be used cruisin the beach roads? What frame and wheels do you have in mind to build on?
Sounds real fun to watch!
Good luck -R

haha - we can drive on the beaches/sand dunes here so that and back county roads are gonna be it’s main use.

if you google triumph tr6 trophy you’ll get an idea of what I’m goin for visually (some what).

stock frame - and spoke wheels off a 74 that will be running a dual disc.
 
Sounds wonderful
stock frame - and spoke wheels off a 74 that will be running a dual disc.
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This sounds very cool, looking forward to the progress!

Maybe clean up the roughness in the ports,

Smoothing out the ports is on my list of standard things to do when the head is off

Found a lot of discussion on this but not found a really detailed description. Curious about it if I have my head off again, but very nervous to screw something up. I’ve seen the discussion of WHY to do it, not as much about the HOW. You guys have any advice or references to point to? (Not trying to hijack!)
 
This sounds very cool, looking forward to the progress!
Found a lot of discussion on this but not found a really detailed description. Curious about it if I have my head off again, but very nervous to screw something up. I’ve seen the discussion of WHY to do it, not as much about the HOW. You guys have any advice or references to point to? (Not trying to hijack!)
All I'm referring to is knocking the rough edges off the walls, without reshaping or enlarging them. In other words, not a proper porting job. For info on a proper porting job, look for a thread from @Jack .
 
All I'm referring to is knocking the rough edges off the walls, without reshaping or enlarging them. In other words, not a proper porting job. For info on a proper porting job, look for a thread from @Jack .
I'm going to be doing a thread on port clean up sometime in the next few weeks. I'll be sure to post lots of pics.
 
Ok so I e got quite a few figment issues to work out and things to fabricate so the first order of business is to make this thing a roller.

I’ve blasted the wheels and hubs and will be painting them later this week or next. since this will be living 3 miles from the coast where we’re soaked in fog most of the year (my favorite part about living here) and this is intended to ride on the beach I am gonna be skipping the chrome finish and polished aluminum on a few things that require too much maintenance around here and take away from actually riding rims and hubs being one of them.

anywho... in my attempts to start getting my forks together I’ve run into what looks to be a problem.

bike was another guys project and the tapered bearings were already installed. - I did double check and they are fully seated.

Should the stem of the triple sit this low in the top???

I pulled the bolt on my 76 and the stem does sit below the top of the triple, just not this far.

I am thinking - turn down the top locking but just a bit to have the top triple sit just a bit lower.

Am I missing something here???

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Off on a side note,

anyone know if this under seat tray, splash guard and battery flat for under the seat hump were a production item???

they seem nicely made although I won’t be using them - judging by the welds the previous owner did on the seat hoop I KNOW he didn’t make them.

gonna be cutting the seat hoop off and putting a stock style hoop back on to run a fender.

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