weld crank shaft pin or not?

[dyna962007]

Dealer is doing engine upgrade on my 07 Dyna.
moding to a 103 with Andrews cams, porting, polishing and flowing heads, etc
The issue arose after the fact about Tig welding the crank pin. some say its needed and some say even on stock HP motors that the crank is sometimes a problem. mine is supposed to be running in the neighborhood of 125hp when done.
At this power, is it ony a matter of time to having a problem with crank if unwelded like some say will happen??
Mike

[BVBOB]

Truing and welding can be done at an affordable price from site sponsor Hyperformance, however, even after welding you will still have the crappy tapered piston pin end of the connecting rods.

[sublime]

I have decided to wait on my build until I have the money to get the bottom end upgraded as well. Going to send it and my 107" pistons off to Hoban's (Darkhorse) to get trued / balanced / new connecting rods / welded... They will also be doing the Timken conversion on my bottom end... I doubt I will top 120HP, but I know my bottom end will hold up

[arealinvestor]

Originally Posted by dyna962007

Dealer is doing engine upgrade on my 07 Dyna.
moding to a 103 with Andrews cams, porting, polishing and flowing heads, etc
The issue arose after the fact about Tig welding the crank pin. some say its needed and some say even on stock HP motors that the crank is sometimes a problem. mine is supposed to be running in the neighborhood of 125hp when done.
At this power, is it ony a matter of time to having a problem with crank if unwelded like some say will happen??
Mike

Balance,weld,true,& plug it!!!!If they can't do it send it to Hoban brothers who can surely get the job done!!!!

[Flashkev]

Originally Posted by dyna962007

Mike

to VTF

[ejk_dyna]

good one flashkev...

first if your dealer can get you an honest 125hp out of a 103...then you have one hell of a dealer

ideally you would want to do the timken conversion to the case and weld the crank. both of these deficiencies work together in creating crank problems on high powered builds.

lots of guys do neither and wind up ok...how lucky do you feel???

[hdryder]

Originally Posted by ejk_dyna

good one flashkev...

first if your dealer can get you an honest 125hp out of a 103...then you have one hell of a dealer

ideally you would want to do the timken conversion to the case and weld the crank. both of these deficiencies work together in creating crank problems on high powered builds.

lots of guys do neither and wind up ok...how lucky do you feel???

Agreed. The tapered rod ends can be swedged and the piston pin bushing rereamed. This will lock the bushing for spining.

[CaptVic]

Originally Posted by dyna962007

Dealer is doing engine upgrade on my 07 Dyna.
moding to a 103 with Andrews cams, porting, polishing and flowing heads, etc
The issue arose after the fact about Tig welding the crank pin. some say its needed and some say even on stock HP motors that the crank is sometimes a problem. mine is supposed to be running in the neighborhood of 125hp when done.
At this power, is it ony a matter of time to having a problem with crank if unwelded like some say will happen??
Mike

Weld the crank. I had a 103 with 94 hp that blew the crank.

[TXCHOP]

Originally Posted by CaptVic

Weld the crank. I had a 103 with 94 hp that blew the crank.

Same here. Just got another bike in that was 89/92 and the crank is getting pulled to go to Hoban friday. It's getting welded! Well the only good thing about the crappy cranks is it keeps us indy's eating!

[arealinvestor]

Damn I missed that, 125hp out of a 103????? You better search for a better stealer because that scares me!!!!!! Someone is pulling your leg!!!!

[sublime]

Originally Posted by arealinvestor

Damn I missed that, 125hp out of a 103????? You better search for a better stealer because that scares me!!!!!! Someone is pulling your leg!!!!

I am doing 107", GMR heads, Woods 408-44 cam and current estimates are 110-115HP TOPS.. I will be happy with 110 as long as I have a nice torque curve...

Not sure how hot a 103" would have to be to produce 125HP. Will that be a big peak number with a crappy torque curve? Will it be streetable on pump gas?

[dyna962007]

hey guys thanks for all the help and nice welcome.
Well this dealer is a very well respected, and the oldest HD dealer here in Saint Louis.
The guy who does the engines has some pretty good credentials and does lots of racing builds.
Now Im not one to believe every bullcrap story and they may be blowing smoke up my tailpipe but that is what they say and they have in house dyno numbers to give me so lets see.
In fact, I called the company I bought my intake from out in San Diego CA about how well the intake was going to flow with this set up and they too do motor builds on these and tell me the average 103 they build runs about 122hp
These were the guys at Cycle Visions with the MO-FLOW intake so who knows guys.
Ok so anyway, I want to put together a comprehensive list of exactly what is being suggested here that are must do things for a 103 build with this kind of HP.
Lets see if I can get this right:
1. Timken Bearing upgrade
2. Weld, balance, true and plug the crank
3.tapered rod ends to be swedged.
4. Piston pin bushings rereamed.
Anything else guys?
Oh and one last question. I did not intend to pull the bottom of the motor originally.
now that I am, should this change the scope of my project? I mean, should I be doing something diffferent now since IM having to pull the bottom apart?
thanks Mike

[sublime]

This is my entire build:

GMR Head porting, CC'ed and milled to make 10.2:1 compression
Stock jugs bored / honed for JE 107" pistons
BC Gerolamy Throttle Body Prep
New lifters
Screamin Eagle tapered adjustable pushrods
Hoban's Darkhorse Timken Bearing install, crank trued, new h-beam rods, balanced with new rods / pistons, plugged and welded...
Screamin Eagle Billet Cam Plate
Woods TW-408-44 cams
VPC92T clutch hat / Screamin Eagle clutch spring
of course gaskets / bearings etc. required to tear down / put together the engine properly...

This will be combined with my rhinehart true duals, arlen ness big sucker and Thunder Max Auto Tune..

Tuning by RC Cycles...

Should end up with an easy 110HP.. I am hearing possibly 120.. I really don't care about the peak number, I am looking for rock solid reliability, big broad torque curve...

[dyna962007]

Originally Posted by sublime

This is my entire build:

GMR Head porting, CC'ed and milled to make 10.2:1 compression
Stock jugs bored / honed for JE 107" pistons
BC Gerolamy Throttle Body Prep
New lifters
Screamin Eagle tapered adjustable pushrods
Hoban's Darkhorse Timken Bearing install, crank trued, new h-beam rods, balanced with new rods / pistons, plugged and welded...
Screamin Eagle Billet Cam Plate
Woods TW-408-44 cams
VPC92T clutch hat / Screamin Eagle clutch spring
of course gaskets / bearings etc. required to tear down / put together the engine properly...

This will be combined with my rhinehart true duals, arlen ness big sucker and Thunder Max Auto Tune..

Tuning by RC Cycles...

Should end up with an easy 110HP.. I am hearing possibly 120.. I really don't care about the peak number, I am looking for rock solid reliability, big broad torque curve...

Thanks buddy, I will take all this information to heart. mike

[compressor#v]

dyna962007, 120hp from a 103" is perfectly believeable. We've seen a few 95" 120hp builds, from Mike52 on another forum, Mike Roland, and Hillside.

J. Sachs, NW Guy 4 fun, and others have posted dynos with 120+hp from 103"ers as well. If the builder pays attention to detail, (and there are some who work at dealers who will) then it's very doable. Ask your builder if he's doing the crank work or sending it out. If sending it out most that do it often will take care of the issues associated with the weak areas in the assembly. Do the Timken conversion and you'll be GTG.
Best of luck.