Starting a 900 build

[DA71FX]

Ok, well the time has come to admit I have a problem.....My name is Dave and I am addicted to old iron....The paint on the 76 FXE is barely dry and I have just gotten to the first oil change and I am all ready starting a new project. I have a very healthy pile of IH Sportster parts and most of a 69 XLCH. This bike is really a collection of parts that has been growing under the bench. So this is not going a 100 point restoration. I am thinking Frisco/Norcal style sporty...which is really the bike I grew up wanting. from the time I was 7-15 my father had a 69CH built in that style and it really stood out in Bristol CT. So while I am not recreating that bike, I do want to do something in that vein. I was thinking stock rake, no stretch, painted and molded frame 4 over tubes, some shiny bits....remove everything that does not make the bike go.  Not planning on stroking it at the moment....but since this will be a bar hopper and back road blaster, I am thinking hard about performance work....So I am open to suggestions. I was thinking good head work compression cams and a mikuni carb. Really need to decide If I want to run drums or period correct discs. I want to keep it to parts that I could have acquired in the in the 70s or 80s. The one thing I am looking for is a 15 inch rear wheel....So let the suggestions fly

[sharkoilfield]

Well; I didn't start riding until about 1968...and I was about 1500 miles north of San Francisco. Sounds like an excellent idea. A SU may be more appropriate than a Mikuni. Everyone I rode with wanted a 16" rear wheel, that was the "big twin" standard. And motorcycle tires were available in that size. 4" over w/o rake or stretch would be nice...keep us posted

[DA71FX]

16 inch might be the way to go. And  I have always liked the SU I've been running them on my shovels for 25 years so I do have a few. Though I did have a mikuni on a stroked 68xlch it was a very nice carb

[Racepres]

16 inch might be the way to go. And  I have always liked the SU I've been running them on my shovels for 25 years so I do have a few. Though I did have a mikuni on a stroked 68xlch it was a very nice carb

A Round Slide??
That is what would have been on the Originals...

[DA71FX]

Yes round slide mikuni VM. It's what was on my 82, my friends 71 and my dad's 69....but mine was picked up at Keene in the early 90s from someone who couldn't tune it and swapped it out for a Bendix....I pulled it off my bike when I sold it because the buyers wanted to run his super B

[DA71FX]

After bouncing some ideas off my dad he mentioned that he thought he gave a set of S&S 4&7/16 stroker wheels to his friend and he never used them.....a phone call later the wheels are on their way here.... now I probably need to get pistons made.....

[JW113]

I've never done a 900 stroker, but you may be able to get away with using stroker plates and stock pistons. If so, might be easier than custom pistons. Having done a 4-5/8 stock to an XL1000, I probably would not do it again. It's kind of a PITA dealing with clearancing the case and rerouting the oil drain holes, and in fact the stock stroke motor can be made to run quite well. But carry on and keep posting, this will be fun to follow. I am also a big fan of the Frisco chopper look.

cheers,
-JW

[DA71FX]

JW, you are 100% right about the PIA that this will bring......but at least  i wont have to relocate the oil returns if I keep the stoke under 4.5 inches....I've been through that before, it can be a real pain.....I stroked my , 82 with the S&S kit and I built a stroked 66 with 5 inch truett Osbourne wheels and Trock jugs back in the 90s that was a very involved project.....I would likely never build a big bore IH again...but  having a pair of good pistons made by venolia is not that hard...

The real pain is finding parts that used to be very common when I started this game...that are now virtually unobtainable...in the late 80s though mid 90s many chopper parts (the quality ones) were being taken off and replaced with billet stuff...and many of the chopper parts were still available...Iron heads were not antique relics and museum pieces  they were affordable used bikes. What really burns me is I purged most of my sportster stash years ago to make room for some more shovel stuff.....on a side note the 76 FXE has been a real blast...not sure how i feel about the electric leg...since it is only my second bike in 30 years with one..and I sold the 82 XLH in 94...so its been a while...

[JW113]

Sounds like you know what you're doing, looking forward to the progress. I did not know that oil return hole relocation is only required beyond 4.5", that's good information. Throw some pics our way if you get a chance. We love pics.


-JW

[SP33DY]

JW, you are 100% right about the PIA that this will bring......but at least  i wont have to relocate the oil returns if I keep the stoke under 4.5 inches....I've been through that before, it can be a real pain.....I stroked my , 82 with the S&S kit and I built a stroked 66 with 5 inch truett Osbourne wheels and Trock jugs back in the 90s that was a very involved project.....I would likely never build a big bore IH again...but  having a pair of good pistons made by venolia is not that hard...

The real pain is finding parts that used to be very common when I started this game...that are now virtually unobtainable...in the late 80s though mid 90s many chopper parts (the quality ones) were being taken off and replaced with billet stuff...and many of the chopper parts were still available...Iron heads were not antique relics and museum pieces  they were affordable used bikes. What really burns me is I purged most of my sportster stash years ago to make room for some more shovel stuff.....on a side note the 76 FXE has been a real blast...not sure how i feel about the electric leg...since it is only my second bike in 30 years with one..and I sold the 82 XLH in 94...so its been a while...

Unfortunately Venolia folded up. They made me a set of pistons for my 4-5/8" stroke Ironhead a few years back. I called them last year for some more custom pistons. The lady who answered the phone said they were through and she was just there until the remaining inventory was gone.

I did get some from JE. I got extra sets because JE got bought out by another company and I was afraid things would change there sooner or later. I would have to go upstairs and look but I think I still have one set for a 4-5/8" stroke 900 and one set for a 4-5/8" stroke 1000.

I think MAHLE is starting to offer custom pistons for Harleys.

[DA71FX]

Thanks for the info, venolia used to be good because they would do sets of 2, I'll call J&E and Ross.... hopefully I'll get somewhere

[nibroc]

J&E will want ya to buy more than 2 pistons  .. 

[Racepres]

And... Last I used Ross we needed More than 2 also..

[DA71FX]

Yeah, last time I used them I had to do 4. It's why I stopped using them but when choices are limited....

[saltcaveminer]

Stroking the 900 is something I did in 1974. In fact I still have the bike. It was my first Harley. I'll keep this short so not to have people fall asleep. Back in the day we would add a reinforcing collar around the counter shaft boss inside the tranny case. It's a weak spot. Also the breather gear needs to be ground down due to the timing difference. The 72 and later valve is recommended instead of the earlier part. S&S Cycle had a full guide to stroking the 900. Go with the bigger Manley valves. Lastly the Mikuni is a very good carb for the Ironhead. Salty