128" build jitters

[fairlydangerous1]

I know there have been some posts about losing a gear in transmission after big bore builds but is it becoming that common?  I have a 2019 114 with 468 and 2-1. High torque, low HP now and am just planning on added the cubes with injectors to the current build.  A couple friends said if I stay under big HP I should be fine. 

I get there is a certain risk with builds (had many done and only had one failure (it was a tranny build mistake) and this damn internet gets me to reading too much.

What are you builders seeing out there?  I'm willing to take some risks, if I went with different cam and head work and no 128" I would still end up around the same torque numbers but probably more HP anyways.

[kd]

I think you will find the 3rd gear failures are also in the twin cam models but relate to how you use the extra power.  Hard shifting WFO and getting traction is where it occurs. The 3rd gear seems to be a bit lighter or the ratio is too wide maybe.  Either way it is usually brought on by the way you are using the the extra power.  The Baker GrudgeBox transmission is 40% stronger and likely for that reason.

[Goopdienes]

if your on facebook at all look up bagzilla hes running close to 200 hp on stock trans and they took it apart to inspect for damage and it still looked like new.

[No Cents]

  George isn't shifting that tranny by foot either...his thumb is doing the shifting for him.    He sells the kit.
A lot goes into how you make your shifts as kd stated. You damn near have to be zoned in as one with a stock tranny to go along with that bigger horsepower if you want to give the tranny any chance of living. You need to shift as cleanly and smoothly as you can...with "no" nonchalant shifting, thinking you'll be just fine slipping it into the next gear @ 4500 plus rpm's. The more throttle being applied, the more accurate your shift points need to be with a stock tranny.
   But this is just my opinion.

[Don D]

Not mentioned but consider payload and gearing as factors.

[fairlydangerous1]

Thanks guys. Exactly the kind of information I'm looking for.

[HD/Wrench]

I had one on the drum and it blew 3rd out under very light load The guy that owns it is not a hot rodder they are hit or miss no way to know .. my 124 rg that i drag race has been fine other break for no real reason . I stepped down as a vendor so not sure if I can post the like or the video .. but if you are on FB you can go see it your self . it broke badly , I was shocked to say the least .

[fairlydangerous1]

In it's current form I run the 468 with otherwise stock 114 and stiff clutch springs.  Dyno'd torque is around 128ft lbs through first few gears but HP maxes at 103.  I like the way it is with just me on the bike but looking for this same feel with Wife on the bike. Was thinking big bore kit would get me there without going crazy.  I ride it somewhat hard but don't power shift. Front end just starts to lift off the ground on some shifts so I would think it would have gone if it were going.  I guess there is no rhyme or reason why one goes and another doesn't.  Just a crap shooting and do I feel lucky........punk?!  I guess I do.   If I'm wrong, TechTalk will be one of the first to know.

[Hillside Motorcycle]

I know there have been some posts about losing a gear in transmission after big bore builds but is it becoming that common?  I have a 2019 114 with 468 and 2-1. High torque, low HP now and am just planning on added the cubes with injectors to the current build.  A couple friends said if I stay under big HP I should be fine. 

I get there is a certain risk with builds (had many done and only had one failure (it was a tranny build mistake) and this damn internet gets me to reading too much.

What are you builders seeing out there?  I'm willing to take some risks, if I went with different cam and head work and no 128" I would still end up around the same torque numbers but probably more HP anyways.

S&S cylinder kit, and their .475.

[joes124]

George at Star Power / Star Racing has a few videos posted on the web and explains that running a stock clutch and shifting way above the torque curve allows the clutch to slip some upon engagement (after the shift) and that contributes to saving the stock transmission too.  In the video you can hear the slippage.

[fairlydangerous1]

What does "shifting way above torque curve" mean?  Shifting at an RPM beyond where torque is rising?  Couldn't find the videos.

[sbcharlie]

a stock transmission with back cut gear and REM isotropic super finish works quite well in hi horsepower engines sbc

[joes124]

fairlydangerous1

instagram georgebrycestar posted 9/21

[1workinman]

George at Star Power / Star Racing has a few videos posted on the web and explains that running a stock clutch and shifting way above the torque curve allows the clutch to slip some upon engagement (after the shift) and that contributes to saving the stock transmission too.  In the video you can hear the slippage.

Yea that what I saw and he also he has a tech every Tuesday at 6 I think pretty sharp guy . He mentioned his basket also .

[Hillside Motorcycle]

If the clutch is slipping, I'd be leaning in the direction of not making it slip??

[fairlydangerous1]

If the clutch is slipping, I'd be leaning in the direction of not making it slip??

My thoughts exactly.