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Shaggy
12-11-2003, 11:05 PM
I've got a 45" WLA bobber that is fun but EVEN the bombcanned flame paint job won't get it going fast enough.
Does anyone know if it is the BSA or Triumph tranny that can be adapted.

manyolcars
12-11-2003, 11:30 PM
how fast do you want to go? mine will run 80. a different trans will still have 1 to 1 ratio high gear. go with a bigger motor sprocket for more top end, SU carbs are the best, use hi compression aluminum heads, copper headgaskets, the large intake and then WR cams if you can. The B&H foot shifter will allow you to run off and leave other 45s but do not increase top speed

CTFuzz
12-12-2003, 12:20 AM
Manyolcars is correct...in the old days stock 45 trannys were replaced with the big twin tranny, not for more top end but because the 45 trans (as you know) has the primary on one side any the drive on the other. With this set up the trans tends to twist in the frame but using the big trans(74"-80") with both chain on the same side (left) the trans will stay in place.......I have put rather large trans. sprockets on 45 inchers but you do loose most of the low end.....bottom line, they ain't fast.

CT.

long island vic
12-12-2003, 01:26 AM
thy are called 45 for a reason.... but any 59 or down pre uunit bsa or trump will fit... how bout putting a evo sporty unit on the frame u will go real fast

Stone
12-12-2003, 02:31 AM
Got any pics?

Hansen
12-12-2003, 03:17 AM
I've heard you can stroke the flatties with the crank and rods from a indian chief, or something like that.

gives you something like 58"

if you want to get even crazier you could look into adapting a kh/kr top end, better breathing yet

burndup
12-12-2003, 03:42 AM
Just sell it to me cheap and you can take the cash and buy a used rice-rocket and go as fast as you want!

http://www.jalopyjournal.com/ubbthreads/images/graemlins/laugh.gif

hatch
12-12-2003, 08:13 AM
Now.....THIS is a good tech post!!!!!...any more ideas??......Manyolkars...are you talking about the WR intake?...can I just clean out my WL?

I have the aluminum heads...how about a small amount of milling on them?

Thanks.....hatch

Flat Ernie
12-12-2003, 08:32 AM
All the easy stuff has been mentioned:

Motor Sprocket bigger (stock for most Solos was 29 - they make 31, 32, 33) - you lose some off-the-line, but gain freeway speed capability. 1st gear is pretty low, so it isn't too bad.

Better carb - SU is probably best, but Mikuni is cheaper.

Drag pipes

Tranny swap - pre-unit Brit bike trannys can be adapted to get 4-spds. Doesn't necessarily help top end (depending), but definitely better ratio spacing!

If you want to get into it some - they are repro-ing DD/DR & WR cams these days. They ain't cheap for the set, but... You can also use K/KR or early Sportster cams, but this requries machine work to the cases. KK cams will also work (if you can find some)

Then there's the 45 magnum - not or the faint of heart as it requires serious & major alterations to your engine.

If you're just after more top end, step up to an 18" rear rim a-la WLA. It ain't much, but it's a little...

Good luck!
http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

Rocknrod
12-12-2003, 08:47 AM
If you want more power... use pipes that connect... ya get some scavanging like on a set of headers.

My .02

hatch
12-12-2003, 08:49 AM
Thanks Ernie...What is the original application of the SU that works on these?...are they available "new"??

I'm looking to keep mine a flathead, so that leaves out the sportster top end conversion.

I didn't know the hot cams were being re-popped...that would be a help.

I'm not gonna ride like I was on my old stroker, so the stock trans is OK for me. But...the top end gearing is something I will do.

Good tips.....thanks....hatch

CTFuzz
12-12-2003, 10:08 AM
Hatch.......check your PM.

porknbeaner
12-12-2003, 10:16 AM
[ QUOTE ]
Thanks Ernie...What is the original application of the SU that works on these?...are they available "new"??

I'm looking to keep mine a flathead, so that leaves out the sportster top end conversion.

I didn't know the hot cams were being re-popped...that would be a help.

I'm not gonna ride like I was on my old stroker, so the stock trans is OK for me. But...the top end gearing is something I will do.

Good tips.....thanks....hatch

[/ QUOTE ]

Sifton still makes hot cams for all the flatheads. Most of them are old Connely grinds. Can't remember the numbers but I'm sure that they know.
We used to use the SUs carbs from a Volvo (about '59 or so) if I recall they were about 38mm. You can get 40s from an older Jag, but they were overkill on the small motor.

Flat Ernie
12-12-2003, 04:05 PM
The SUs came on Brit cars as previously mentioned. I don't know if you can get 'em new or not. I've never used one and am more familiar with the Mikunis due to my ATC racing days as a kid. They're cheap & plentiful.

45 Restoration (http://www.45restoration.com)
45 Restoration has the repop DR cams (I think), but they get over $400 for the set. They also sell a Mikuni kit, but you can piece it together yourself for much cheaper.

45 Parts Depot (http://www.45partsdepot.com)
45 Parts Depot is supposedly repoping the WR cams, but their website says "coming summer 03", so I don't know if they've got them or not.

To be honest, I don't know what the difference is between DR & WR cams and would imagine they'd be similiar, if not identical.

Victory Library (http://victorylibrary.com/books1.htm)
Victory Library has books/booklets & parts (including stroker flywheels just like Indian Chief)

KNS Cams (http://www.victorylibrary.com/kns/camnotes.htm)
KNS Cams regrinds your cams. Info on the victory page.


Good Luck!
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gettingreasy
12-12-2003, 07:41 PM
My dad has a stroked Sport Scout, 57ci with cheif wheels. I think the Indian trick is for indian only but, I think you could try UL 80" wheels or the JD 74"ers. The DR cams are the same(I think)as the WR, but there was a difference between pre war and post war WR cams. There was a guy in No. California named Barry Shunk(sp?)he was a cam grinder that did mostly flat head stuff, both the H-D and Indian, his cams are still around think lots or overlap and Mild lift WTFO throttle.
-Jesse

Shaggy
12-12-2003, 08:52 PM
Well my plan for the bike includes Indian chief flywheels which strokes it to 54 inches (which I already have) and the better breathing K-model upper end (which i still need to find)

Any help on finding the K upper? or the tranny.

I still have some carb and brake work to do but next summer it should be going reliably. It aint bad for a high school graduation gift though.

Flat Ernie
12-12-2003, 09:13 PM
[ QUOTE ]
I think the Indian trick is for indian only but, I think you could try UL 80" wheels or the JD 74"ers.

[/ QUOTE ]

Lots of folks used the Chief flywheels in the WL engines. Not sure you could even close the cases on a set of UL wheels. Remember the 45 engine was considerably smaller. Someone is, however, repoping the stroker wheels and Victory is selling them (can't find the original supplier) for reasonable (~$260)

Lots of folks just change intake cams as the exhaust outflows the intake by quite a margin stock.

As mentioned, you can machine the cases to accept early Sportster (pre 70) cams which opens up a lot of options if you're really hard-over.

Is Sifton still around?

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

hatch
12-12-2003, 09:13 PM
Since a K model is a flathead, how much HP would you gain for the expense involved??..If you are gonna change the top end, why not use the sportster (magnum) conversion?

Hansen
12-12-2003, 09:41 PM
[ QUOTE ]
If you are gonna change the top end, why not use the sportster (magnum) conversion?

[/ QUOTE ]

cases arent up to the task, unless you like putting around like an old man.........which negates any power increases

but I'll digress to some more knowledgeable people........

Shaggy
12-12-2003, 10:02 PM
Well I might just be a punk 18 year old kid but I really know my 45 harleys.

First of all the big twin trannies will not work because they are backwards of a 45, the chain goes out the other side

Next I Aint runnin one of them New fangled Mikuni Thangs

chief flywheels will drop into a 45 but the shafts are different so with a slight modification or switching shafts you get 53 or 54 cubes

K model cylinders will bolt on a 45

A 45 magnum is just a high priced bomb 45 cases will not stand up to a newer sportster upper


Anyone know the specific english trannies (years+makes) which can be used?
Can any one help me find a K upper or the right english tranny

hatch
12-12-2003, 10:27 PM
I would still like to know how much HP increase do you get with a K model topend??...I think I might know where I can get one, but is it worth the expense?

Hansen
12-12-2003, 10:28 PM
from one 18 year old punk to another......got any pics of that thing?

hatch
12-12-2003, 10:43 PM
How about this beauty???? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

Hansen
12-12-2003, 10:52 PM
I'll take that! gotta love a ripe old bike

how bout the other guy?

hatch
12-12-2003, 10:57 PM
Maybe this one??? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

Flat Ernie
12-12-2003, 11:07 PM
Well I might just be a punk 18 year old kid but I really know my 45 harleys.


Maybe I'm reading you wrong, but don't get defensive - no one said differently. You're just getting a lot of opinions and good questions.


First of all the big twin trannies will not work because they are backwards of a 45, the chain goes out the other side


Oh don't let that stop you - swap wheels to a left-side drive. They can be made to work. If you're willing to stick K cylinders & Indian flywheels in yer engine, why let something as trivial as changing your drive side bother you? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif


Next I Aint runnin one of them New fangled Mikuni Thangs


Remember, SUs are foreign too and Mikunis, while newer than SUs, have been around quite a while - a lot longer than you! http://www.jalopyjournal.com/ubbthreads/images/graemlins/wink.gif


I would still like to know how much HP increase do you get with a K model topend??...I think I might know where I can get one, but is it worth the expense?


Not loads, but better than port/polish/relieve stock flathead probably. They redesigned the ports quite a bit on the K I believe. While I've never done it, I don't think it's quite a bolt-on mod though...

Good Luck!
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gettingreasy
12-13-2003, 02:34 AM
For being a punk 18 year old you may know your 45's but you don't know jack about trannys(this coming from a punk 20 year old), a pre unit tranny is a Direct drive constant mesh just like a big twin tranny, both of them the power comes in on the left and leaves on the left. Don't be such a bitch about a Mikuni not being trad enough, so put a fuckin Amal on it and quite whinning.
-Jesse

gettingreasy
12-13-2003, 02:39 AM
Thanks Flat Ernie I didn't know that the Cheif wheels fit right in. I know that shaved or porkchoped UL wheels will fit in them, but unshaved wheels will go right in a Pan or a Shovel with not much of a problem, sorry my mistake.
-Jesse

Flat Ernie
12-13-2003, 09:13 AM
Thanks Flat Ernie I didn't know that the Cheif wheels fit right in.


Well, "fit right in" might be a bit optimistic, there will be some minor machining involved from what I understand (I've never done it!), but size-wise they're a good fit. That's why if I decide to go stroker, I'm going to use the new stroker wheels - they're set up to accept all HD pins & shafts, so it IS a bolt-in.

Tell me more about cutting UL wheels (not that I'll ever find a set, but hey...) Is it only the thickness/width that needs to be shaved? I thought the OD would be too big by enough of a margin to make it unfeasible.

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

Rocknrod
12-13-2003, 09:29 AM
Any of you guys fooled around with the idea of beefing up the cases? Weld in some more metal like they welded up the WWII battle ships? Two big honking pieces of steel, lay a weld on each side and build it up! Just as strong if not stronger then the surrounding material.

You guys know where they crack? What kind of clearance is needed? I guess the other that you could do is make a steel girdle for the bolts on the cases if thats where they crack...

Other one you could do is weld the oil passages compeletly shut going to the top end, run external oil lines up to the top...

Just throwing out ideas, I'd like to build one... just dont have enough info on em http://www.jalopyjournal.com/ubbthreads/images/graemlins/blush.gif

manyolcars
12-13-2003, 09:48 AM
The bottom line is--if you want a bigger engine, go get one and leave the 45 alone. After a lot of time, money and work, all you will end up with is a loud expensive noise as overstressed parts explode. The 45 is a great machine and there is nothing wrong with mild hop up, but modifying cases, magnum topends and tranny swaps are futile.

CTFuzz
12-13-2003, 12:45 PM
Hey..51F-3, I may be a 56 year old graybeard punk, but I do know my Harleys......the reason one would install a big twin transmision in a 45" is BECAUSE the primary and drive chains are on the same side. During very hard driving the trans would tend to turn in the frame of a 45, this would loosen the chains......get the picture?

CT.

leadsled1953
12-13-2003, 04:23 PM
i had a 42 wla years ago.you may want to get a bigger motor sprocket[i think the wlrd racing 45s had a bigger spocket]check the heads for the compression.it should be stamped on the side of the alumimun heads.you may want to up that.i used to know a place that delt with hop up stuff for the flatheat harleys but that was 30 years ago. check on the net.

Mojo_AL
12-13-2003, 05:39 PM
I've never done it myself, but here's what I've read.

-The model you were looking for is a BSA M20, although any pre-unit brit bike tranny will work great.

-You will need to figure a way to build a primary drive, I'd go with a brit bike open belt.

-You will also need to machine the outer diameter of the Harley motor sprocket and the inner diameter of the brit motor sprocket. Fit the brit outer to the Harley inner. I think people weld them together usualy.


Check this out

http://victorylibrary.com/BTRAN.htm

They shoud have all the info you're looking for.It doesn't look like rocket science (SProcket science http://www.jalopyjournal.com/ubbthreads/images/graemlins/tongue.gif) to me, so you could do it without ordering the booklet.

Hope this helps

Rocknrod
12-13-2003, 07:13 PM
... I've never been called practical... And ya, maybe modifing the cases would be impractical... but the weight of the whole package when setup as a 45 is what attracts me. Anyone have a diagram of where they crack? http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

gettingreasy
12-13-2003, 08:19 PM
Flat Ernie, the od does need to be shaved and I'd seen a set that was pork chopped so she'll rev higher/quicker and decelerate when you get of the gas in a turn. my dad always was into flat head hillclimbers and was once talking with an old timer, the man said he built a trap door in the bottom of the cases(WL 45's), weld two channels and put a piece of sheet metal(22 ga I think)and used a mag advance unit(the lever kind w/ cable)to pull on the sheet metal. Here's how it woked, at the bottom of the hill you'd rev the piss outta your motor and right when you would let go of the clutch you push the lever and it would dump all of the oil out the bottom of the motor and it would rev about another 5-800 rpm, remember no shifting so the more you rev the quicker/faster you go.
-Jesse

Flat Ernie
12-14-2003, 06:15 AM
you'd rev the piss outta your motor and right when you would let go of the clutch you push the lever and it would dump all of the oil out the bottom of the motor and it would rev about another 5-800 rpm


That sounds, well, insane. But racers are known to do whatever they can for that extra little bit...seems like a total loss oil system with a gaping hole in the bottom of the cases would prodcue the most HP then, eh? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

My only concern with the big twin flywheels cut down that much would be balancing. Which I'm sure they didn't bother with back in the day, but on a daily driver...still, an interesting concept.

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

Reverendcolin
12-14-2003, 08:17 AM
Nothing you can do will make a 45 fast or dependable.

Wait a minute. I take that back. You could always get a big twin motor, tranny, frame and...Never mind

No matter what you do some guy with a 350 cc bike will blow you off. So you'll be slow and look stupid. There are things you can do to get a little speed out of it (heads, carb lightened fly wheels etc.)and drilling and wiring everything is a big to-do.

It would be a waste of time and a pain in the ass to install a big twin tranny in that frame. BTW I have a nice tight turtle top tranny I can let you have for $900.

Get a copy of Questions and Answers
"A Mechanical Manual for the Beginner and the Experienced Motorcyclist"

The copy I have is 1984 and from:
Antique Cycle Supply, Inc.
Cedar Springs, Mich. 49319
(616) 636-8200

There’s lots of specs and info on old American Motorcycles and a nice section on Speed essentials for flatties and other motorcycles.

If you want something that’s old and you can make go fast get a knuckle, Pan or Shovel.

manyolcars
12-14-2003, 09:02 AM
******Nothing you can do will make a 45 fast or dependable.****** Only the unknowing would make such an absurd statement. The 45 is THE most dependable Harley ever built!!!!!!!!!!!!!!!!!

hatch
12-14-2003, 09:59 AM
Maybe he meant fast AND dependable. That would be tough. But just dependable???...no doubt about it!!!...I think WWII proved that.

I know I would like a little more power, without spoiling the looks of the bike. I think with some of the ideas and links this can be possible. My days of tire shredding strokers is over, but I would like to be able to ride with some degree of safety and comfort at 50 mph...and a little bit of extra power when needed to get out of a dangerous situation.

This has been an interesting thread.

manyolcars
12-14-2003, 11:22 AM
Hatch, the 45 will run 80 mph or more in stock form. The WWII Harleys had a metal tab on the gas tank saying 'Do not go over 85". Its a great machine for around town and backroads. If you want to ride with big twins, they will out accelerate you. You will not want to run on the Interstate Hiways. The 45 will do it but its running wide open. I have a 1946 that I have been riding 28 years. I have other 45s too. Simple modifications I mentioned above are great, but chopping up the frame for a big twin transmission is STUPID. Magnum top ends overstress the lower end and transmission and frame and require chopping up the frame. The 45 is what it is. If you want to go faster, get a bigger Harley and dont ruin 45s!!!

hatch
12-14-2003, 11:48 AM
I don't plan on doing anything radical on the bike. I will freshen up the top end...new pistons, rings and valves and maybe put the hotter intake cams in it. Thats it for me. Maybe change the final gearing to a 31 tooth countershaft sprocket. I don't think the bike will ever be on the interstate as long as I own it.

Flat Ernie
12-14-2003, 03:34 PM
Nothing you can do will make a 45 fast or dependable.


I take exception to the dependable portion - the fast portion is all relative. But isn't that what hot rodding is all about though? Taking something old and massaging it to do its best?

I imagine by your criteria, there's probably nothing I can do to my Flathead Ford to make it fast & reliable either. And by modern computer controlled standards, maybe you're right, but that's not why I fool around with them.

Anything can be built bigger, better, faster. The latin phrase, "How fast do you want to go?" is translated directly into "How much money do you want to spend?" - Case in point: You want to make the 45 bottom end bullet proof? Carve one out of billet instead of using 60 year old castings. Then slap on that Sportster top end and see what happens.

I drove a 48 WL daily for about a year and a half and it always cranked on the second kick and never left me anywhere. Even when I finally killed it with a melted piston (high speed lean-out), it still ran on one cylinder and got me home!


If you want something that’s old and you can make go fast get a knuckle, Pan or Shovel.


So what you're saying is is that I should ditch my Flathead Ford & put a Y-block in, right? But why stop there? A heavily breathed on Knuck, Pan, or Shovel is no match for a mildly warmed over Evo or TC88. You wanna drive a 53 Vette, a 67 Vette or an 03 Vette?

Bottom Line: Old things (especially mechanical) have gobs of character. If they're a little bit slower and maybe even slightly less reliable, isn't it worth it?

If not, go hop in your Honda and bling down the road comfortably, reliably, economically, and quicker than me! Courses for Horses!

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

NOTE: No Honda drivers were injured during the formation of this post.

Gruntis
12-14-2003, 04:32 PM
Yep" I have to argee with Manyolcars I to have been throwing a leg over 45s for about twenty years as well, dont take much to make them ridable, gearing is the answer for sure my latest got a 33t front sprocket stock rear I relieved the top end and slightly pumped up the compression this ol heap will run 65 all day, Dont forget these things was made over sixty years ago, I carnt remember the last time a 350 for the same period got around me whislt riding

Gruntis

hatch
12-14-2003, 05:18 PM
Gruntis...did you shave the heads to raise the compression, or find some different pistons? The replacements I have found are 6 to 1 compression ratio. Is that what you used?

Also, could you give a little more detail on relieving this motor?

Man...I can't wait till spring!!!!

Shaggy
12-15-2003, 10:05 PM
Hey HATCH keep in mind the maximimum compression you can reasonably put on a 45 is 7.5 or something like that according to (I think??) Tom Sifton. I know its low for a flathead but it becomes inefficient after that its what i've read.

A with running a big twin tranny isn't there a axle or sproket problem?? I heard something like that from a couple people. Well anyway I'm going english

P.S This might be my first 45 but not my first Harley I built my 58 165 by myself when i was 11 and when i was 5 i was the youngest member of the antique motorcycle club -but now i've been corrupted by Hot Rods.

Thanks for the help

hatch
12-15-2003, 10:15 PM
Interesting thought about the compression...anybody got anything else on this topic???

Dan
12-16-2003, 12:09 AM
I imagine the flathead harley is similar to the flathead ford in that there is a limit you can go on compression before you get diminishing returns. Seems like on the ford it was somewhere around 7 or 8:1 even with aftermarket heads. Someone with more knowledge about the harley will have to chime in on what their limit is. The flathead combustion chamber can only handle so much. Those old bikes are awesome, I love examples from every era stopping around the shovelhead era. Wish my old ironhead was as reliable as the old flatheads! Can someone explain the differences in the WL designations?
Someone the other day asked about good chopper/bobber sites and I hate to say it but the HAMB is probably one of the best, way more/better info here than The Horse website... I am afraid that is why people keep asking bike questions here...

Flat Ernie
12-16-2003, 02:47 PM
As mentioned, I'd have to guess the limit on CR is based on the transfer area of the head - similar to Flathead Ford. Interesting side note, one of the Flathead Ford books (can't remember which one) has a diagram of a WR? cylinder that's been step relieved as a comparison to the chapter on Flathead Ford relieving. HD probably did this so they could mill the head more trying to find the best return-on-investment for flow vs CR.


Can someone explain the differences in the WL designations?


WL - Solo 45
WLA/WLC/WLD - Military (D = AL heads, C = Canadian)
WLD/DD/DR - Factory hi-po/racing versions
WR - Factory Racer

There are several others, along with the G (servicar) designations. I cheated and copied these outta my 45 Restoration catalog, but I think this info is on their website too.

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

Flat Ernie
01-02-2004, 07:29 PM
Since the last post on here, I've been doing a lot of research for my project & here's a little of what I found - mostly from Victory Library's 45 Performance Book - well worth getting their big book if you're serious about mucking around with these little engines.

Truet & Osborn make the repro stroker wheels that bolt-in & use all stock components. S&S still make stroker wheels for the 45 in lots of strokes, but you have to use Sportster rods - which isn't a big deal, just something else to buy/acquire.
Currently, no one is producing stroker pistons, so you either have to run stroker plates or have custom pistons made - JE will do them for about $120 ea(!!)
The WR cams are being reproduced, but there is a timing issue with them & they are such a mild grind, you're probably better off with reground cams or adapting K or early XL cams.
Lots of good info & some really smart folks (including many folks who support the aftermarket stuff) on this board:
Flathead Power Forum (http://www.flatheadpower.com/cgi-bin/ubb/forumdisplay.cgi?action=topics&forum=Talk+Flathead s&number=2&DaysPrune=10&LastLogin=)

Enjoy!

http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

buckweet
12-18-2005, 08:02 AM
I've got a 45" WLA bobber that is fun but EVEN the bombcanned flame paint job won't get it going fast enough.
Does anyone know if it is the BSA or Triumph tranny that can be adapted.

the BSA tranny fit's.

weet

BZNEIL
12-18-2005, 10:50 AM
A little OT but I have been thinking about getting a flathead to ride around town. This would be my first street bike,I have ridden dirt bikes for 20 years. Would a 45 be a bad choice for a first bike or should I think about something newer thats not a rigid.

bzneil

caffeine
12-18-2005, 11:17 AM
buy a panhead.

ENGINENUT
12-18-2005, 01:32 PM
I once experienced a same brand/different model parts swap with a WLA that may have some potential for you.In 1959 a friend bought a cheap(50.00)WLA and when we made it run found it had one ventilated piston.I had just pulled a set of .010 pistons from my 54 KH so we fitted them to the 45 and then we found the pistons from a 55 incher had a different pin height so the pistons barely touched the head.We added some head gaskets to get running clearance and put her on the road.It was the fastest 45 we ever fooled with(all basically stock).Possibly you could use the KH higher piston height to advantage-trimming the piston crown or relieving the head for squish area and compression improvement.The slightly higher ring position in the cyl was not a problem in our engine.I seem to remember the KH was relieved considerably and HD had lowered the ring positions accordingly.I have a HD publication "specifications & instructions -competition racer model KR-KRTT" that well shows the cylinder relief shape and dimensions in usable detail.Also remember the K's used an aluminum head with NO gasket.I have also seen this done on a Indian sport scout to raise compression for competition.Have fun.

Flat Ernie
12-18-2005, 09:50 PM
I once experienced a same brand/different model parts swap with a WLA that may have some potential for you.In 1959 a friend bought a cheap(50.00)WLA and when we made it run found it had one ventilated piston.I had just pulled a set of .010 pistons from my 54 KH so we fitted them to the 45 and then we found the pistons from a 55 incher had a different pin height so the pistons barely touched the head.We added some head gaskets to get running clearance and put her on the road.It was the fastest 45 we ever fooled with(all basically stock).Possibly you could use the KH higher piston height to advantage-trimming the piston crown or relieving the head for squish area and compression improvement.The slightly higher ring position in the cyl was not a problem in our engine.I seem to remember the KH was relieved considerably and HD had lowered the ring positions accordingly.I have a HD publication "specifications & instructions -competition racer model KR-KRTT" that well shows the cylinder relief shape and dimensions in usable detail.Also remember the K's used an aluminum head with NO gasket.I have also seen this done on a Indian sport scout to raise compression for competition.Have fun.
Using the K-model pistons in the WL is a common trick - reading through Victory Library's tuning papers, there's a lot of talk about this. Check out the flatheadpower forum. I think I even saw Panic posting on here recently (he's the author/compiler of the Victory Library)

gas4blood
12-18-2005, 10:39 PM
Use a carb off of a 74. My Sport Scout uses a Chief carb. It runs a lot better than before. An HD 45 just isn't a fast bike. But it should keep up with traffic OK. I agree with the others, play with the sprockets a bit. That's what I do. 30 years ago the shovel, pan, and knuck guys didn't like to ride with me too often, they said it was too hard on their bikes. The HD won't run with an SS, but it should be suitable, a bobber is even better. You aren't running a 16" on the back are ya? Those things kill the acceleration. Try some porting, the usual flatty stuff. How fast do you want to cruise? I don't see a lot of point in changing the trans. unless you just want to do it for fun. Enjoy it for what it is, a neat old bike, I think that's what you're already doing!

sgary
12-19-2005, 02:24 AM
I've got a 45" WLA bobber that is fun but EVEN the bombcanned flame paint job won't get it going fast enough.
Does anyone know if it is the BSA or Triumph tranny that can be adapted.


I have some old info and part #s to swap the bushings to roller bearings and I think some other internal stuff.PM me if you want the info.I have it somewhere,I haven't looked at it in 15 years.