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generatorshovel
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Date Posted:05/19/2007 8:15 PMCopy HTML

Well, I've given up cigarettes to fund the salt habit, and things are moving along smoothly.The FZR head and barrell lost No4 cylinder,(Yamaha's loss, Honda's gain)the water galleries and oil returns have been plated, the crankcases are nearly finished their stay @ the welders shop and will be decked soon (its a "laydown" engine now.aka ct110 style), the crank has been modified to take the FZR rod (slipper big end bearing), the piston (FZR) is booked in for a ceramic crown coating, and I've contacted a friend who'll balance it all for me.The FZR cams have been shortened, with2 ofNo3 cyl's lobes being reduced to a 23mm circle where the oil seal will run , and the other 2 lobes are gone, leaving a 22mm camshaft extension to be used with outrigger bushings which will double as the oil feed to the cams.The belt pulleys are on their way from Gates, for added "bling"CDI ign is on the wish list (Boyer Bransden,,$700,,ouch, with adjustable rev limiter and special coil)Dunno 'bout it being ready for 2008's timetrials, 'cos I need to build a new frame yet, and source some better wheels, and speed rated slicks,,and so on , and on,,,,,,but,,ya never know? 'till ya try.Tiny
brucifer #1
  • Rank:Platinum Member
  • Posts:327
  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:05/20/2007 8:41 AMCopy HTML

I have a lot of respect for ya Tiny, you're a true hot rodder. What you're doin' is just too cool! I'm curious what that things gonna dyno when you're through. Keep us posted and good luck to ya. Bruce
generatorshovel #2
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:05/20/2007 10:06 PMCopy HTML

The only dyno it'll see is that big white salty one that's only open once a year, so long as it don't rain.

My next goal is 85 MPH, but a predicted 17 BHP pushing a not too aerodynamic ME through the air is going to be a BIG ask, but I'll be happy if, when the time comes to fire it up, it holds together for 10 minutes, the rest would just be a bonus.

My last successful (and 1st) salt run seemed like  the longest kilometer I've done in my life, with the EGT hovering around 1300 degrees BEFORE hitting the tst timing light, rolling off to 2/3rd throttle, reducing ex temp to 1200 degrees and averaging  71 MPH over the measured distance, thats why I'm going for water cooling, ceramic coated piston, and cooling oil directed to the under side of the crown.

Will it work ? who knows?

http://i156.photobucket.com/albums/t24/generatorshovel/08build.jpg


 

Tiny

Motoracer838 #3
  • Rank:Gold Member
  • Posts:121
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:12/15/2007 4:37 PMCopy HTML

Just saw your photobucket pic, that is so cool.  It looks like youv'e used a lower end from a 100/125 and layed the cylinder down, how's it progressing?

Joe 

generatorshovel #4
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:12/23/2007 9:13 AMCopy HTML

Yeah Joe, well , almost right,,it's a CB 125 bottom end , picked 'cos of its positively fed primary side main bearing oiling , and the fact it was sitting on top of the honda engine pile when I started the project.

the cylinder angle is now 11 degrees from horizontal (like the CT 110 it's based on)

If anyone's thinking of doing this modification, I strongly suggest you " borrow " some of grandma's Vallium pills first.

While milling the crankcases to take the new sleeve ('99 FZR in a '93 cylinder) I broke into the main oilGallery , the one that supplies EVERTHING !,,1 week before christmas, when all the Tig specialists want to sit on their butts and get drunk !

I quickly cut and rolled up an aluminium patch to cover the break thru and approached the man who's done all the other Tig'n on the engine, and suprise suprise, in 2 hrs , the job was done ! Thanks Jamie .

The new frame is almost finished, which will put me into a new class , A/F 175 ,and I'm setting up the engine in it , today was cardboard cutout day (paper dolls come later) .

Another job looming is to work out what lift / duration Yamaha use on the FZR , compare the readings to some after market cams , and settle with a figure that'll meet my 9,000rom + needs.

Then there's the problem arising when you take a mostly splash and gravity fed camshaft lobe(s) / cam followers / valve spring setup and lay 'em down so gravity only oils the valve covers instead.

I've cut the side out of and old clutch side cover and rigged up a starter motor to spin the oil pump (yeah , the thing that's designed to supply hi flow / lo pressure to a roller big end bearing, and make it deliver hi pressure,low flow to the new slipper big end bearing and dump the extra flow via a pressure reliefe valve -something else I had to make ) so as to check my pressure / flow to all that needs oiling , without actually starting the engine.

Here's some more pics (not up to date )

 

Motoracer838 #5
  • Rank:Gold Member
  • Posts:121
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:01/06/2008 2:15 AMCopy HTML

 

Keep the pics coming.

Joe 

generatorshovel #6
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:01/07/2008 10:55 AMCopy HTML

Reply to Motoracer838(05/19/2007 2:15 PM)..
Ill keep updating the photobucket site (there's a few newies in it since the link posting), check whenever you feel the need.
I had some success with the cam(s) timing, it turns out the ebay'd cams were megacycle "factory road race" grind, wooohoooo !
Tiny
generatorshovel #7
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:02/27/2008 5:57 AMCopy HTML

Well, the oil pressure / flow test was a disaster [EMOTE]smiley-cry.gif[/EMOTE] , it seems my 'ol eyes missed a secret oilway/crach behind the main oil gallery, in the area of the new cylinder deck, plenty of oil for the r/h side of the piston skirt, but that's all.

  Plan "B" time
I always had concerns that once the gearbox / big end/ r/h main bearing, and the top end eagerly consumed the available oil supply, the big end slipper bearing would starve for hi pressure oil feed.

Out with the thinking cap again.
I tapped into the main oil gallery @ the front of the engine, adjacent to the cast gallery coming from the oil pump, filed the original gallery, and fed the oil into a modified air rifle barrel [EMOTE]smiley-laughing.gif[/EMOTE] , which fits into the clutch cover, bypasses the original centrifical filter (on the end of the crank) and feeds the oil PAST the main bearing oiling supply hole in the crank, assuring full pressure to the big end bearing.
the air rifle barrell is machined to 8mm, then 7.7 mm, and finally, 6mm , (the size of the center of the crank, past the main bearing supply), this is threaded to 8mm x 1.25 to hold it in place in the clutch cover, and the thread will also help to keep the oil @ 55 PSI before finding its way past the main bearing oiler, and into the clutch area.
There is also a 55 PSI pressure regulator in the circuit,and a diffuser to feed the cams, and the oil cooling nozzle (for piston crown) then the excess oil pressure is dropped down to 10 PS! , fed back into what's left of the original oil gallery, to feed the gearbox shafts, all other oil is dumped back into the crankcase.


No pics as yet, but this week end SHOULD see a successful test, of the bottom end pressure / flow, then, the head's feed, and the oil nozzle's turn.

Life was never meant to be easy ?

Hopefully,,the bike will be ready for when the salt dries out, probably in march 09 ?

Tiny
Swiss #8
  • Rank:Diamond Member
  • Posts:1254
  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:02/29/2008 11:42 PMCopy HTML

If you put a gauge on this, let me know what it reads at different rpms.  Yoshimura stated over 30 years ago that it was the needle and roller bearings that gave these engines their high rpm capabilities and that those bearings didn'r require high oil pressure.  I doubt that it will be anything close to 55psi.  Never hear of anyone actually testing pressure on one of them, just checking for oil flow.

Swiss
generatorshovel #9
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:03/01/2008 2:31 AMCopy HTML

Test No 2,,,partly successfull , part failure,,,time for yet another 'case split,,,damn !

Swiss, the only reason I need such high pressure is to feed the yamahaha slipper type big end bearing, and the camshaft , the rollers used in the Hondas dont need much pressure, just high flow, and theres plenty of that, plenty of pressure too if you reduce the area the oil has to escape through, once pressurised.
Now my oil is escaping through the main bearing outer race retaining groove, but how it gets there is a mistery, 'till I have a look, the CB 125 cases have a few differences to accomodate the main bearing oil feed, and its possible I've found another, which I'll have to reduce in size, or rely on the oil feed through the inner race and block completely?
I get 60 psi before the bypass opens, then it fluctuates a lot, as if theres another valve somewhere, as it fluctuated even more when my bypass is taken out of the equasion.
I have no trouble getting 60 PSI @ 100 oil pump RPM's, I just hope I can get rid of enough oil thru the by pass to stop the pressure going thru the roof, and over stressing the pump / drive / pinion gears.
Frustrated Tiny[EMOTE]smiley-undecided.gif[/EMOTE]

UPDATE,,,,,,,,,
It seems I had one of the "O" rings behind the oil pump slip out of place before the pump was tightened, I found the feed side "O" ring was split and not in its correct position, hopefully I'll get some new O rings tomorrow and try again.
Too bad I split the cases before I removed the pump, but , then again, I needed the practice setting up the kickstarter shaft one more time.
generatorshovel #10
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:03/02/2008 1:15 AMCopy HTML

The good 'ol 60 cent  "O" ring caused my probs,,wooooooooohoooo, I can move forward again now, checking the top end oiling, the piston oil cooling nozzle, but I'm confident it'll be all good, although I might still have to drill  a .05mm in each cam to lube the cam lobes and cam followers, seeing gravity is now my enemy due to the new cylinder angle.
The pressure still fluctuates between 50 and 65 PSI when the oil pressure bypass valve opens and shuts, but this will reduce as the oil flow increases with the oiling of the rest of the parts, and allowing for hot , thinner oil when the engine is actually running.
I've noted full pressure is reached at about 500 oil pump revs (1/2 crank speed) and remains constant up to the maximum 1000 revs my drill can handle, and the force needed to spin the pump @ full pressure isn't very much at all, which is good, due to the limited amount of horsepower that's going to be available.
Tiny [EMOTE]smiley-smile.gif[/EMOTE]
Motoracer838 #11
  • Rank:Gold Member
  • Posts:121
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:03/02/2008 4:31 AMCopy HTML

Tiny it's good to see your project moving along. based on your tests, it looks like I don't have to worry about a pressure drop on my engines when I add oil coolers to both of them (they desperatly need it, on a 70 degree day they were both excedingly hot after the motos.)

When you fire up your bike,
does it return the favor.  Joe
generatorshovel #12
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:03/02/2008 7:02 AMCopy HTML

It's an all good news day today, the sight of oil spewing out of an engine @ the right pressure and the almost right amount of flow (I need to back off the feed to the cams)is almost enough to make a grown man c [EMOTE]smiley-cry.gif[/EMOTE] tears of joy, keeping the oil inside the engine will be another challenge though, especially @ the cam covers.
Theres no need to drill oiler holes in my cams, the spent oil from the cam bearings is more than enough, and my sneaky valve spring oiler holes thru the head  castings worked a treat too.
I'll take some pics tonight of the mess of hoses, clamps and tee's that will need a re-design before final re-assembly, but it's getting close now,,hopefully, the backwards has vanished from forward backwards land,,,finally [EMOTE]smiley-laughing.gif[/EMOTE]
Tiny
[IMG]http://i156.photobucket.com/albums/t24/generatorshovel/bushs.jpg[/IMG]
XL-erate #13
  • Rank:Gold Member
  • Posts:148
  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:03/05/2008 4:03 AMCopy HTML

Mr. Shovel sir, I must say, that is one fine and admirable project there! You must have been a vintage Star Trek fan in days of yore? "To boldly go where NO MAN HAS GONE BEFORE!" Really happy to see your progress and step-by-step intelligent resolution of problems. It's more than a sad thing here stateside where people have one thumb in their mouth and the other up their boomer, drooling with snot running out their nose as TV massages their minds into a semi-liquid slime state as a substitue for THINKING! 

Glad to see your noble contributions to the fine art of diligent thought and your deviously clever solutions, most excellent!

XL-erate
generatorshovel #14
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:04/04/2008 10:23 AMCopy HTML

HO HO HO,,'eerewe go Very Happy
Oiling system,,complete and tested, thanks for the oil tip chris Wink
30 PS! with the chinese drill @ full noise in reverse (the pump test driver)
Oil cooling jet squirts like a teenager with the stamina of a bull Very Happy
FINAL ENGINE ASSEMBLY is on for tomorrow , gone is the plumbers nightmare and the Kg of worm clamps, replaced by some reeeeal flash braided steel lines, if bling is ya thing, its got its share now Rolling Eyes
Happy Happy , joy joy...... Smile
T'fer
XL-erate #15
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  • Posts:148
  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:04/05/2008 1:40 AMCopy HTML

Good news, man! Just asked about this over on that V45 thread and here's the answer. Sure rootin' for you on this run!

XL-erate
Motoracer838 #16
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  • Posts:121
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Re:DOHC 161cc LSR project update

Date Posted:04/05/2008 2:52 PMCopy HTML

I can't wait to see the latest pics. Good luck on startup.

Joe
generatorshovel #17
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  • Posts:152
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Re:DOHC 161cc LSR project update

Date Posted:04/06/2008 2:30 AMCopy HTML

HUGE steps in the right direction,,,at last !
[IMG]http://i156.photobucket.com/albums/t24/generatorshovel/Slug.jpg[/IMG]
Ceramic thermal barrier shown on piston crown
[IMG]http://i156.photobucket.com/albums/t24/generatorshovel/4Valvehead.jpg[/IMG]
Just what every XL head needs to have
[IMG]http://i156.photobucket.com/albums/t24/generatorshovel/RH.jpg[/IMG]
[IMG]http://i156.photobucket.com/albums/t24/generatorshovel/LH.jpg[/IMG]
[IMG]http://i156.photobucket.com/albums/t24/generatorshovel/Waterfront.jpg[/IMG]
What ! water cooled XL ?
[IMG]http://i156.photobucket.com/albums/t24/generatorshovel/WaterL.jpg[/IMG]

As you can see, progress has been good this weekend , but still need a big bucks Boyer Bransen
CDI ignition system , megga voltage coil, and a rev limiter, (I have a feeling she'll pick up revs REAL quickly
, and I don't want to risk valve float if I miss a gear or 3)
Tiny
XL-erate #18
  • Rank:Gold Member
  • Posts:148
  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:04/06/2008 2:57 AMCopy HTML

Holy cow! Holy Smokes! Holy Brisbane, Tiny, that is astounding! Ultra trick no doubt! Only a few steps away, but I would guess they're long steps. Great job and I do believe a record will fall, hard, and break in a couple of dozen pieces.
Swiss #19
  • Rank:Diamond Member
  • Posts:1254
  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:04/06/2008 5:18 PMCopy HTML

Tiny, did we ever talk about exhaust?  What are you planning to run?

Swiss
generatorshovel #20
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:04/07/2008 3:48 AMCopy HTML

Reply to Swiss (04/06/2008 11:18 AM)
Tiny, did we ever talk about exhaust?  What are you planning to run?

Swiss


No we didn't Swiss, but I'm searching,,trying to get some info on open meggies, but the technology seems to have dissapeared with the 'ol fellas who learnt thru experience,and passed on befor ever reaching a computer,,lol
I have a program or 2 , and numerous formula from the local "bucket racing" aussies, but most use reverse cone meggies, I want all my power above 7,500 rpm,,up to possibly 10,000 rpm.
Any input would be greatly appreciated mate.
At the moment it's looking like a 30mm ID header, about 18" long, with a slow taper megaphone exiting about 2 1/2 ", for starters anyway,,I plan on comparing the "seat of pants" comparison using the rev cone meggy I made for the last engine, but I got a feeling , although the midrange was brilliant, power started to drop after 7,000 rpm
Tiny
Swiss #21
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  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:04/10/2008 7:35 PMCopy HTML

Tiny,

What was your primary length and primary diameter and meg length and diameter for the old pipe?  The diameter shifts the tuned rpms up as the dia. increases.  The length shifts the torque curve higher as the length gets shorter.  So basically you will need short and fat!  HA!HA!  I will crank out some numbers for you, but would like to know what you ran before on the old engine?  What are the valve sizes in the new head?  Bore and Stroke.  You probably mentioned them in earlier posts, but easier to gather together if they are all in the same post!


The reverse cone won't hurt your top end at all if it is correct.  Will take some playing with the outlet angle and diameter, but that is easy enough to do with either dyno run or speed runs for top end in lower gears.  You will need to set a MAX Redline rpm for me to tune around.  What is the absolute max you will run it to?  You have to remember that you need a little bit of a powerband so that you don't fall off your acceleration when you are shifting through the gears.  A little wider powerband will also allow you to run a bit wider gap between your top two gears.  If you fall out of the powerband at speed, it will be tough to pull it back up for your to gear!

Swiss

generatorshovel #22
  • Rank:Gold Member
  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:04/11/2008 9:21 AMCopy HTML

Here's a few numbers for you to play with Swiss.
!st the old pipe.
Exhaust valve diameter  25mm
Exhaust valve opens 79 deg. BBDC
Exhaust valve closes 45 deg. ATDC (Tighe 399 grind)
Primary pipe ID               27.5mm
Primary pipe length (to "look" stock(ish) 680mm
Megaphone length          310mm
Meggy max ID                 60mm
Cone length                    80mm
Cone opening                 30mm
Bore / stroke     56.5mm / 55.4

New head
Exhaust vale diameter 2 X 21mm
Exhaust valves open 39 deg. BBDC
Exhaust valves close 20 deg. ATDC
Exhaust port dia @ exit 30.5mm
Maximum primary pipe OD  43.5mm
Bore / Stroke    65.5mm / 49.5mm

max HP (1990 FZR 600 spec) @ 10,500 rpm
Max Torque                             @ 8,500 rpm
This would be the maximum safe rpm the valve train could handle (maybe 11,000 if needed)

Tiny
generatorshovel #23
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  • Posts:152
  • From:Unknown

Re:DOHC 161cc LSR project update

Date Posted:04/12/2008 3:03 AMCopy HTML

 FORWARDS/BACKWARDS LAND HAS RETURNED Cry
I just had the rug pulled from under me,,and I feel worse than I did the day the postponement of '08's salt lake meeting was announced  :(
  The final assembly ended up not so final,,,the bolts I bought to make cylinder studs out of,,had dodgy threads on the end (shoulda checked,,I know), causing the nuts to bind, giving a false torque reading, and NOT pulling the head down properly,,,well,,it gets worse.
Once the head and barrel came off for the 17th time to fix the studs, then re-assembled today, torque'n the head down,,10 ft/lb,,no probs,,20 ft/lbs on 1, 2 and 3,,ok,,,no4 felt wrong,,mmmmmm? tear down time,,again,,FUCK !!!!!!!!!!! the U beaut helicoils that were 'sposta spread the load better than the 8mm original size,,did'nt,,,now I have a r/h crankcase on the bench and need to find a better way ????????????
Tiny
Swiss #24
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Re:DOHC 161cc LSR project update

Date Posted:04/12/2008 3:28 AMCopy HTML

OK Tiny,

You are going to run LSR and you need your peak power close to your peak rpms.  With your shorter stroke, you should be safe up to close to 12k rpms.  This is figured because the Factories don't typically run their engines at redline and peak power being the same rpm or close.  They typically have a fair amount (like 15% or more) ..  10,500 rpms is only at aout 4,000fps of piston speed.  This is considered tame street bike rpms with your stroke length.  12,000 would be reasonable for an absolute redline for a street engine.  For a built "race spec" engine you are looking at just under 14,000 rpms for redline.

Now that is alright, we can still tune for the given constraints that you want to use.  I would suggest 10k for peak power, which should give you a strong build to close to your redliine.  Typically I like to tune for about 85% of redline, but that is for general racing and not for Top Speed LSR runs where you need o pull strong right up close to redline. 

Your old pipe was kind of confused according to my formulas.  The primary pipe diameter was good for about 9k but the length was peaking out at about 7k, which was probably close to your torque peak and not your peak power rpm.  For a race engine I feel that you want to tune for the max power peak rpm and not the torque peak.  The megaphone and reverse cone will give you all of the midrange that you want or need if they are correct.  Your old meg was too small for the engine that you had it on.  The diameter was right for about 5.5k and not giving you the best benefit of the meg design for the required diameter.  It was tuning for you way down in the low to mid range because your head pipe was too long. 

For your new engine everything will change.  This will sound kind of radical, but it will work for you.  I converted everything over to mm for you which is what you are used to working with.

Diameter                     1.325"/33.65mm
Total Tuned Length     20.4"/518.2mm
Pipe length                  18"/457.2mm
Meg length                   17.4"/442mm
Meg OD .065"wall tube 3.3"/76.2mm

This should tune for 10k rpms and give you a strong powerband to pick up your speed.

Swiss

Gto to run out to dinner, I will add some more to this later tonight.
Swiss #25
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Re:DOHC 161cc LSR project update

Date Posted:04/12/2008 5:19 AMCopy HTML

OK, the finishing touch is the reverse cone.  Without it the powerband will be really strong but very narrow.  Typically you should run a 45 degree angle or steeper on the cone.  The longer taper is supposed to give a broader over-run at the top end, but you don't need that and if your power drops at 10.5k to 11k it is good for maintaining your redline.  The outlet typically should be about 1/8" larger than your inlet/primary pipe ID.  This isn't science, just experience.  It actually depends a lot on how the meg works with your cam timing and that can require a little experimenting with outlet diameter and reverse cone angle.  You should leave a little bit of port overhang where the pipe and port meet or set up a small A-R cone inside the pipe.  This will keep the tuning pulse from going back past your exhaust valves and contaminating your inlet fuel/air mix.

Hope this helps.

Swiss
generatorshovel #26
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Re:DOHC 161cc LSR project update

Date Posted:04/12/2008 9:50 AMCopy HTML

Thanks HEAPS Swiss, your blood's worth bottlin'

Iv'e also figured I should use Keenserts to replace my failed Helicoil, and the other 3 that have'nt failed (yet).
Now I have to weigh up the extra strength of the heavy duty Keensterts (14mm OD) with my  "not much more than that" deck width, compared to the light duty Keenserts with a 12mm OD (both available in m8 x 1.25 ID )
Then I have to find someone who stocks them locally,,or buy online. (nothing's easy when the closest "big" town is 200 miles away)
On your imp. / metric conversion Swiss,,lol,,I was taught the Imp system @ school, until 2/3rds way thru High school, in ''66, when we had to forget everything we had been taught, and go metric.
I still travel in MPH ('67 HD) and mentally convert the distances back to MPH when working out the distance I have travelled, even though the mile signs are'nt mile signs anymore,,lol,,they are posted every 10 k's,,sound confusing???? well, the MPH Harley speedo helps, and its just as well, 'cos I also work in miles per gallon,,kilometers per litre does nothing for me, nor do newton meters, gimmee good 'ol reliable ft/lb any day.

Damn,,Iv'e missed the start of the speedway,,,
Tiny
Swiss #27
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  • From:USA

Re:DOHC 161cc LSR project update

Date Posted:04/12/2008 4:44 PMCopy HTML

I have used Keenserts and like them better then the heli-coils.  For that sized engine the smaller Keenserts shoud be fine.  From the pics that you posted, I am guessing that you did a LOT of welding to fit the new cylinder base material into the old cases.  Of course, welding the plate into the case drops the heat treat of the material by about 2 heat treat grades for each time you weld it.  You probably had to make multiple passes in order to fill the material in and the result may be that your material is now close to "T-0" for heat treat level.  In other words, SOFT!  For the Keenserts, I would recommend using the longest ones that you can fit into the case at that point in order to give some strength to the connection.
8mm dia. studs will be much stronger than the stock 6mm pieces.  Don't know if you can get the studs with "rolled" threads for better quality.  I have found odd sized studs by going through the ARP catalog and ordering by length and thread rather than application.  i don't know who in Australia might make the ARP level quality bolts, but Aussie's are famed for "creating" odd-ball stuff from literally nothing!  You can of course get the cases heat treated.  Probably want to do that without the thread inserts in stalled.

Good luck with it.

Swiss
generatorshovel #28
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Re:DOHC 161cc LSR project update

Date Posted:04/20/2008 3:37 AMCopy HTML

The engine now sits on the bench again, in the same state it was a week or so back,,but this time,,,hopefully,,it'll stay this way.
20 ft/lb torque and the cylinder studs are still attached to the crankcases,,phew !
A question for Swiss
"You should leave a little bit of port overhang where the pipe and port meet or set up a small A-R cone inside the pipe. "
Do you mean if the pipe ID is larger than the port, this should do ?
A-R cone,,like primary ID swollen, then reduced back to original ID , for about 1 1/2 " (my LSR friend made this set up near the port on his 151 MPH HD with open drag pipes, and it improved the tractability, compared to 1 3/4 open pipes, which stutter under load about 1,500 / 2,000 rpm, under any sort of load)
Tiny
Swiss #29
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Re:DOHC 161cc LSR project update

Date Posted:04/20/2008 4:49 AMCopy HTML

Yes, like your LSR friend.  You can swell the pipe diameter a bit larger for 1 1/2" from the pipe mount at the head (can even make flats on the sides where the studs hold the pipe on if you are still using studs and not springs)  Then make a port extension that fits inside the swelled area for a length of 1" long.  This kills the reversion pulse from traveling back in to the cylinder and helps the engine run cleaner at ALL rpms.



This is s pic of one of the first AR set-ups that I did for my XL.  I later made an aluminum cone that fitted under the end of the pipe and extended into the primary pipe.  This early one used the stock studs to attach the pipe.  Later I converted to springs like many 2-stroke pipes use.

Swiss

Swiss #30
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Re:DOHC 161cc LSR project update

Date Posted:04/20/2008 4:31 PMCopy HTML

Tiny,

The sidecar racing looks like fun, but the short sleeves and jeans on pavement looks kind of dangerous even at relatively slow speeds! HA!HA!

If you consider destroking the engine, all of the numbers will change for the exhaust.  RPMS will go up a bunch, diameter will change a little and length will change for both the head pipe and the meg. 

Good luck

Swiss


Go soothingly on the grease mud ... as there lies the skid demon! ...





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