1275 or 88 or 90 CID for 4-Speed

[IXL2Relax]

Then, that's great!

So long as you know how deep the water is --- Go for it --- Jump in with both feet flying...

We always enjoy seeing what others are doing with their Sportsters - Post up some pics for us along the way...

You can read about my adventure to get KT on the road - Click on My Motorcycle Chronicles in my signature...

Ride on....


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[juzyHD]

I think that primary configuration on this engines is not suitable for such power.

[schaffersshovel]

i am finishing my 107ci now ,was a 96 inch ,,bigest issue is clutch hub ,,machine a bushing and run sealed magnet in hub as well as a sealed hub bearing ,,, i run a bandit clutch with modified cover ,and do trap door upgrade u will be fine

[Four Speed]

MkC, many of us know exactly what you mean about the great feel of the four-speeds.
These were the lightest of the XLs, so to my mind it plays to the strength of these models
if you lay some your hard earn cash on suspension and brakes and a refit with new Timken
bearings all round. You get a sweet handling ride with plenty of low down grunt that is such
fun when the road gets twisty.

The four-speed transmission does place limitations on how far you can go with power. If you
want reliability and higher power, I would as as a minimum add a Zippers trapdoor,
go for the stronger Andrews countershaft and gears, fit a steel cam-follower and maybe get
the pawl carrier bore reamed and thin wall bushed to eliminate shifting slop while in there.
I also added a modified Hayden tensioner to introduce some shock-damping. I originally
suggested the NUP1009 clutch basket bearing based on advice from an SKF engineer.
Sadly, many of us obtained bearings of questionable provenance. Turns out that genuine
NUP1009 are a rare and seriously expensive bearing. I then opted to fit an SKF "explorer"
6009 which is enhanced over ISO standards and gives you about 15% improvement in
strength. You will still be left with the clutch basket weakness with a scorpion clutch.
Best get into the habit of checking it at the end of each riding season.

Finally, the 94 oil tank upgrade is good idea or think about fitting a lighter Lithium battery.
The weight of an AGM will eventually crack the original oil tank. My HD came with spare oil
tanks. One had a 5/16 inch hole where the mounting bracket had ripped from the tank! I
din't fancy being on it when that happens, so I did the 94 upgrade.

Hope that helps.

[Four Speed]

i run a bandit clutch with modified cover

schaffersshovel, that is interesting. When I was in contact with Bandit they told me
that they did not make a road version of their clutch with an alternator because of
the weak 6009 bearing. Maybe you could post some more details about what you did,
if you haven't already.

[farmall]

Engines are cheap enough you could relocate the side stand (easy to do or have done if you don't weld, and the weld is minimal) and toss a five speed into your rolling chassis then keep or part out the four speed.

Just because a motorcycle comes with a four speed doesn't mean it needs to stay that way and rebuilding a bottom and top end can easily cost more than a complete donor engine.