Suzuki PE250B

[James P]

Hello all. I have just joined the forum and intend to ask for assistance with parts interchangeability for some slight modifications to my PE250B. In the meantime, here is a photo of the bike (which you probably can't see unless you have downloaded the necessary program to circumvent the latest nonsense by Photobucket ):



If you can't see the photo, try this link: http://photobucket.com/gallery/http://s1277.photobucket.com/user/JamesP001/media/DSC06963_zpskbwmnsig.jpg.html

I bought it about 10 years ago with the intention of converting it into a road bike (which I have done). However, I originally had the intention of making it into some sort of "classic super motard" with a disc brake front end and other modern parts, but soon decided to keep it as original as reasonably possible.
The previous owner had been using the bike for classic enduro events. All the road gear had been removed, but luckily the front light and speedometer were included (no rear light though). There were a few minor bodges around the place (not sure whether the previous owner was responsible), but luckily nothing that couldn't be fixed.
As the bike was running when I got it, I was tempted to leave the engine alone. However, I decided to strip it for inspection anyway - lucky I did, as the primary drive nut was about to come off the end of the crankshaft!
Unfortunately, the plastic handlebar switches were beyond repair. I added an ignition switch from a Lambretta, which incorporates switching functions for the lights. I also added an electric horn from a Lambretta (I don't think the B model came with a horn originally). I had the stator lighting coils converted to 12V and the whole lighting system is now regulated 12V AC. The ignition equipment is all original.
I bought a job lot of original B parts from USA. Most of these were scrap, but still good for patterns. Importantly, a restorable rear light unit was included. I managed to find a box of 5 original rear light lenses at an old Suzuki dealer locally.

The carb which came fitted to the bike was a Mikuni VM34 from a Yamaha TZ750! I replaced it with a TM32 flat-slide carb (from an early TS250X I think) which I had previously used on another project bike. I had my machinist make a special flange-to-spigot adaptor for this carb, which is attached using a rubber sleeve for a Mk2 Amal carb. The original air box had a couple of large cracks, so I used a large K&N pod filter on a custom-made adaptor which rests on the frame cross-rail to give some support to the carb.

The original exhaust which came with the bike was in reasonable condition, but had a "crease" in the header pipe. The original silencer was missing and the previous owner had stuck an early RM/YZ short silencer on the end. I decided to keep the original pipe for fixing later and bought a Circle-F system from USA.

Luckily the bike's original wheels were in good condition. The previous owner told me they had been rebuilt recently and they certainly looked OK, so I left them alone. The rear shock absorbers are Hagon brand and looked new, so I left them alone too.
The forks were from a YZ125D and were a little too long. I recently replaced them with a set of PE175/250C/N forks, which are more suitable in the absence of the originals.

I'll add some more details when I have time...

Regards,
James

[LWC82PE]

At first i could not see the photo on here or at the link but i can now. Not sure if its something you adjusted or what i did though. Good looking bike and welcome to the forum.

[James P]

At first i could not see the photo on here or at the link but i can now. Not sure if its something you adjusted or what i did though. Good looking bike and welcome to the forum.

Thanks...its Leith isn't it? I remember you from the Suzuki PE Yahoo owners group which I joined when I got the bike! I've just checked my records and that was 13 years ago...

I (practically) finished the bike in 2006 and got it road-registered for the next 3 years in succession. There were a few things I wanted to change (more on that later), but other projects led to the PE being put on the back burner. It isn't that I lost interest - it was just that I had so many other projects and only so much spare time and money (that hasn't really changed ).

The prospect of low-cost historic registration has led to me dragging the bike out again for the revamp I always intended. The items on my list are:

1. The exhaust is too loud. The Circle-F pipe came with two silencers; a restricted one and an unrestricted one. The former was loud and the latter was even louder. After much experimenting, I ended up adapting a modern FMF silencer. This did quieten it down a bit, but not enough. I have had some success on other bikes with internal stingers (where the stinger starts in the parallel belly section instead of at the end of the reverse cone), so I aim to have the Circle-F pipe modified in this manner. Research and experience suggest that this should drastically reduce noise with little or no effect on performance.

2. When I got the bike, it was fitted with YZ125D forks. There was nothing "wrong" with these, but they were a tad too long. I have since found a decent set of PE175/250C/N forks, which I have rebuilt and fitted (as seen in the photo). This gives the bike a much better stance (and makes it more suitable for road use), but I still want to drop the front end a little more. The stumbling block is the fact that the forks can only be pushed up through the yokes by a small amount before hitting the handlebars. At the moment, I am investigating alternative yokes with handelbar clamps which are set back (like post-1979 PE models), which may allow the forks to pass further through the yokes without hitting the handlebars.

3. Ever since I first got the bike running, there has been an intermittent oil weep from the clutch cover, although seemingly only when the engine warms up. After replacing the gasket a couple of times, I noticed a hairline crack in the clutch cover, which I thought (at the time) was responsible for the problem. Using ThreeBond on the gasket seemed to almost cure the problem, but now I am recommissioning the bike, I'd rather fix it properly. However, now that I have inspected it more closely, I am not convinced that the crack is responsible for the leak - the crack only affects the outer portion of one of the bolt hole bosses (not the main portion of the gasket face) and as such should not allow any oil to leak through. I have lapped the gasket face on the cover and will do the same on the crankcase (I thought I had done this when I built the engine, but now I am wondering ). I am tempted to just reassemble after lapping and see what happens, but I think I'd rather have the crack welded in case it causes further trouble later on.

4. When I rebuilt the engine, I fitted a Barnett clutch kit (friction plates, plain plates and springs). Despite soaking the friction plates in gearbox oil for several months, the clutch would drag somewhat. The springs were also a little stiff for my liking, but I could possibly put up with that. I did notice that the combined thickness of all the Barnett plates was about 0.5mm more than the original (old) Suzuki plates, but am unsure whether this caused the problem. The clutch basket and centre boss spin freely and independently, so I am satisfied that they are not causing it. I'm not sure whether the Barnett Kevlar material was/is more prone to drag than the standard cork (or whatever Suzuki used), but I also noticed that the drag reduced somewhat when the clutch was purposely slipped more than usual (some may say "abused" ). Whatever the case, I have decided to go back to the standard plates and springs. The original (used) plates are all within specification and I have bought some new genuine springs. Funnily enough, the Barnett plates which I have just taken out look almost pristine...

5. The bike came with a NOS genuine Suzuki (Mikuni) fuel tap, although I really wanted one with a reserve facility. After a lot of research at the time, it seemed impossible to find such a tap which would fit the threaded spigot on the aluminium tank. I'll put up with the standard tap if I have to, but I'd be glad to hear from anyone who can suggest an alternative tap with a reserve facility which will fit the tank.

As some of you may have read, I have advertised for info on fork yokes in the Kawasaki, Suzuki and Yamaha sections. I'll put up some details of whatever "solution" I decide on!

Regards,
James

[LWC82PE]

Fuel tap with reserve that fits PE250B tank is RL250 tap. I bought one for the exact same reason.

This is part number - i found the box with part number from the one i bought


Part # = 44300-05115
Part Description = COCK ASSEMBLY,FUEL
Model Count = 12
AS50 1969 50 SPORT AS50 STREET
RL250L 1974 246 RL250 EXACTA TRIALS
RL250M 1975 246 RL250 EXACTA TRIALS
TC120 1967 120 TC120 TRAIL CAT DUAL SPORT
TC120R 1971 120 TC120 TRAIL CAT DUAL SPORT
TC90 1970 89 TC90 BLAZER DUAL SPORT
TS50J 1972 49 TS50 GAUCHO DUAL SPORT
TS50K 1973 49 TS50 GAUCHO DUAL SPORT
TS50L 1974 49 TS50 GAUCHO DUAL SPORT
TS50R 1971 49 TS50 GAUCHO DUAL SPORT
TS90 1970 89 TS90 HONCHO DUAL SPORT
TS90R 1971 89 TS90 HONCHO DUAL SPORT

and the 78 RM top clamp will fix your other problem for sure

[James P]

Nice one - thanks for the info Leith!

Regards,
James

[Terrapista]

Point 4 - same thing happened to my clutch with barnett plates. Just too wide by micro millimeters and returned to oem plates. I am using brintech springs but same as you, clutch is too hard so i guess stiff springs make it drag so will look for oem springs now. Thanks for bringing it up.

[James P]

Point 4 - same thing happened to my clutch with barnett plates. Just too wide by micro millimeters and returned to oem plates. I am using brintech springs but same as you, clutch is too hard so i guess stiff springs make it drag so will look for oem springs now. Thanks for bringing it up.

Good to know I'm not the only one! The free length of the Barnett springs was/is exactly the same as new genuine Suzuki springs, so I doubt that my problem was caused by the springs becoming coilbound (but I will check the number of coils and thickness of wire to confirm). I bought new genuine Suzuki springs because they were very reasonably priced (130 Yen each from Japan) and should do the job nicely.

Regards,
James

[James P]

Fuel tap with reserve that fits PE250B tank is RL250 tap. I bought one for the exact same reason.

This is part number - i found the box with part number from the one i bought


Part # = 44300-05115
Part Description = COCK ASSEMBLY,FUEL
Model Count = 12
AS50 1969 50 SPORT AS50 STREET
RL250L 1974 246 RL250 EXACTA TRIALS
RL250M 1975 246 RL250 EXACTA TRIALS
TC120 1967 120 TC120 TRAIL CAT DUAL SPORT
TC120R 1971 120 TC120 TRAIL CAT DUAL SPORT
TC90 1970 89 TC90 BLAZER DUAL SPORT
TS50J 1972 49 TS50 GAUCHO DUAL SPORT
TS50K 1973 49 TS50 GAUCHO DUAL SPORT
TS50L 1974 49 TS50 GAUCHO DUAL SPORT
TS50R 1971 49 TS50 GAUCHO DUAL SPORT
TS90 1970 89 TS90 HONCHO DUAL SPORT
TS90R 1971 89 TS90 HONCHO DUAL SPORT

and the 78 RM top clamp will fix your other problem for sure

Leith, I've found some pictures of the fuel tap 44300-05115. The brass tube for the "main" fuel supply looks to be of quite small ID (smaller than the outlet perhaps?). Do you think this tap flows enough fuel for a PE250? Have you got one handy to measure the ID of the tube(s)?

Regards,
James

[LWC82PE]

Yes i had considered this and even thought it may be an issue when i posted that info. I will have to find mine on the weekend. I know the tube is small. You wont find it easy to find something else that fits. I know the tube is small. Do you know the size of the hole of the stock tap on the inside? I got a feeling these OMG taps would flow more
http://www.omgitalia.com/en/fuel-taps-for-cross-enduro-trial-and-quad-bikes/

Have a look what is on this site. From memory the thread is M14 X 1.5 but its a bit of a guess. You will need to check..

Usually ebay UK/Europe sites have these OMG taps.

[James P]

Yes i had considered this and even thought it may be an issue when i posted that info. I will have to find mine on the weekend. I know the tube is small. You wont find it easy to find something else that fits. I know the tube is small. Do you know the size of the hole of the stock tap on the inside? I got a feeling these OMG taps would flow more
http://www.omgitalia.com/en/fuel-taps-for-cross-enduro-trial-and-quad-bikes/

Have a look what is on this site. From memory the thread is M14 X 1.5 but its a bit of a guess. You will need to check..

Usually ebay UK/Europe sites have these OMG taps.

When I first got the PE, I thought the fuel tap fitting looked exactly like a Lambretta. However, the Lambretta tap is a little larger and the thread is M16x1.0 (you remember correctly - the PE thread is M14x1.5).
OMG was one of the makers for original Lambretta fuel taps and still makes them, including big-bore versions which flow at least 600ml per minute. Although this is a fairly arbitrary figure, I tend to use it as a starting point for checking fuel flow capability for 175-250cc single-cylinder engines. Although I may accept a tap which flows less than this amount, I would prefer it not be too much less.

I seem to remember investigating OMG when I first built the PE, but the lack of correct thread size meant it was a non-starter. I suppose a special nut could be made to adapt an OMG or other brand tap to the PE tank, but it would probably cost as much as the tap itself!
Unfortunately I haven't got a spare standard PE tap to check measurements etc., but I am wondering whether it is possible to bore out the passages in the 44300-05115 tap to improve flow. The outlet looks to be about 5mm ID (which should be adequate), so it should just be the internal passages and valve which need modifying, along with fitting a larger ID brass tube. However, this involves a bit of faffing about and it would likely be necessary to obtain larger filters to prevent debris in the tank from blocking the passages over time.

Although a quick bit of research shows that mid 1970s TS250s used fuel taps which were shared by some 50cc and 100cc models (as for the 44300-05115 tap), I have no idea of the sizes of the internal passages. Anyone who knows of a more suitable out-of-the-box fuel tap with a reserve function to fit the PE250B fuel tank, please let us know! In the meantime, I will continue the research...

Regards,
James

[tony27]

Do the PE taps thread into the tank or over a threaded boss? My CZ uses OMG taps & I can measure the threads for you tomorrow if needed

[James P]

Tony,

The PE250B tap has a threaded nut which engages with a male thread (spigot) on the tank. From memory, the thread on the tap is left-handed (Lambrettas are like that too) to allow proper adjustment and seating.

I did also find reference to two OMG taps with M14x1.5 thread:

01Z3254030
01Z3254190B

However, I think these both fit into a female thread in the tank, which presumably means the thread is "normal" right-handed.

I'd certainly be glad to know the details of the thread(s) on your CZ tap though...if only to rule it out as an option .

Thanks & regards,
James

[Terrapista]

http://forum.ozvmx.com/index.php?topic=40919.0
Hey James
The above link is a thread for an new aftermarket petcock to suit your model. Unfortunately there is no reserve but if you would like it I can post it to you no charge.

[James P]

http://forum.ozvmx.com/index.php?topic=40919.0
Hey James
The above link is a thread for an new aftermarket petcock to suit your model. Unfortunately there is no reserve but if you would like it I can post it to you no charge.

Thanks for the offer . I have the genuine fuel tap fitted at the moment, which does the job well enough (just without a reserve function ). I am tentatively planning to buy the 44300-05115 tap and measure the fuel flow (for both "normal" and "reserve" functions) - if it is sufficient I will use it as is...if not, I will investigate modifying the tap to improve the flow.
If for any reason I need a pattern fuel tap like the one you now have spare, I'll be in touch!

Thanks again & regards,
James

[tony27]

CZ taps thread into the tank so the opposite of what you're wanting. I wonder how much different they are to the taps Yamaha used at the same time, they used the funny nut as well. I'll check the thread size for you on Tuesday