primary chain replacement

J

jotapip

Guest
Hi Folks,the primary chain on my 1978 Jota is ready for replacement,its ran out of adjustment and is occasionally quite noisy (chaka chaka),i've never replaced one before,iwas wondering if it was within the realms of my abilities to do it myself,is it quite straightfoward and does anyone have any useful tips :D,how often should they be changed ,i've owned the bike for 5 years with only occasional adjustment,also looking at a certain dealers parts list i see that there two types to choose from,triplex or two singles,which is recommended by you guys?....i realise this may seem basic stuff to be asking but we all gotta start somewhere....any advice will be greatfully eaten.

phil.
 

laverdakeith

Hero member
Hi Phil, I prefer a twin simplex set up over the heavy original triplex and always use Iwis chains. The job is fairly straight forward, but not without its pitfalls....I would recomend borrowing the correct primary drive locking tool from the ILOC tool library, failing that an old PO8 Brembo brake pad makes a useful locking tool. If they have never been done you should also look at changing the clutch cush rubbers while you are in there, remove the spark plugs and turn the motor on the starter when removing chain case. If you don't already have a manual, buy one, all of the information you need is contained therein.


    Keith.
 
L

lawrence3

Guest
I'll take this opportunity to put in a plug for Andy.  He regularly posts here and has impressive knowledge of drive chains.  Great customer service as well!
 

andychain

Hero member
Cheers Lawrence

Triplex are available still but the current quality is nothing like 20 years ago.

If you go with the 2 simplex chains I would recommend the big pin variety, G67HP, but others have used iwis small pin, standard cam chain, with good results. Therer is also the Mrec deisel duplex which is still unproven on Laverdas despite there being a growing number in use. Grant is last to take one so ask his opinions on the look of it, as he has not fitted it yet. Once again the only feedback so far is they are very quiet so please those of you iusing them let me know.

You can get these from a couple of suppliers, Jane at Sprockets Unlimited and myself. They are also used in the correct length on Hyundai cars, part number 24361-2A000, just in case you work for a Hyundai dealer and can get them cheap. I would suggest that buying direct fro Hyundai would cost somewhat more than the other sources.

Have fun

Andy
 

Jotahowl

Full member
        Check on what sort of ignition system you have before turning your motor over with spark plugs removed.    Not recommended for DMC's.

        Cheers Shorty
 
G

Grant

Guest
The Iwis duplex chain I just got (less than 24 hours UK to Spain!!!) is a proper piece of kit.
It has big pins which look like they will handle the load well.

The Regina 2 x simplex (brand new) chains that I will now throw away had different levels of slack in them, so in effect it would have been one single chain doing most or all of the work, not a good idea in my book.
I will fit the chain today and will run it on the inner 2 rows of teeth. Should give the bearings an easier time.
Andy reckons the duplex lasts over 100,000 miles in a Merc engine, so I do not expect issues in this engine.
I see it as better insurance than the unmatched simplex chains.
I also got an Iwis camchain from Andy, and that too looks the business. I will fit that later.

It seems to me that we buy service items from our usual dealers as always and expect similar quality, but as has been pointed out it looks like in some cases the manufacturer has 'relaxed' standards (at best) or some other less scrupulous individual has contaminated the supply route with substandard products.

I intend to write to Regina in Italy with proof of the crap quality of brand new chains in their packaging.

This may be an isolated incident for Regina (...) but it affects 2 Regina cam chains I obtained from different sources..
The 4 x simplex primary chains will also be disposed of once correspendence with Regina Italy has ended.
 

Dellortoman

Hero member
Andy

If you were installing a primary chain on your bike (pretend you have a Laverda), which option would you go for - IWIS duplex, 2 x IWIS simplex or IRIS triplex? Or possibly a Tsubaki triplex?

Cheers,
Cam
 

laverdakeith

Hero member
Grant said:
I intend to write to Regina in Italy with proof of the crap quality of brand new chains in their packaging.

  These chains are far from brand new Grant, they have been kicking around for years. My guess is that a bunch of dealers got together in the past and bought a job lot. I have two different types of Regina chain here, both in what apears to be genuine packaging, one type of chain is marked with 3M and uses split rollers I will not use this chain, I've found a good few roller segments in the bottom of primary chaincases over the years....The other type of Regina is marked CHR on the sideplates and it is of very obviously superior quality and more than up to the job.
  No use complaining to the manufacturer, I dare say they would advise against using the 3M chain for our aplications also, your beef is with who supplied the inapropriate chain.

    Keith.
 

andychain

Hero member
Grant thanks mate but the Mercedes chains run for 500000 miles. My old E300 had 675000 on thre clock on the original untouched engine. I did change oil and filter at 3000 miles as do the taxi drivers in Munich where they get literally millions of km.

Andy
 

andychain

Hero member
Cam its a no brainer, I like bullet proof and the Merc chain would give that, having said that Keith runs the standard iwis simplex cam product on his primary and is happy so what the feck do I know. :D :D :D :D :D

Andy
 

andychain

Hero member
Cam I had better explain about the duplex. Although I do not own a Laverda, the principles are the same across all machines. In the same way that the simplex G67HP with the big pin is replacing duplex chain in not only motorcycle primary drives on BSA and Maico amonst others, but also in Jag,TVR and Porsche engines, it is simple to deduce that the duplex big pinned Merc chain will replace the triplex.

Over 1 year ago I put several free samples out to Laverda owners and I know some chains were fitted. To date the only  feedback through a thread was that they are very quiet.

If I were racing a Laverda I would adapt the drive to accept 1 of the G67HP chains and change it regularly as the weight saving on reduced sprockets and chain would be good.

It is also nice to hear that the standard rear chain M106SL is working well on a race machine even tho it is in OZ.

Andy 
 

andychain

Hero member
Keith.

The iwis automotive product has a split roller. Renold and iwis found that with the increased rpm of madern engines even deep drawn rollers occassionally failed. They developed their own split rollers. I cant vouch for Renold but the iwis roller is from a very special sprung steel and the ends are champhered, spelling !!!, this acts a a kind of small shock absorber and it cured the problem. Also a lot of new engines run on bush chains where there is no roller to fail.

Along with the blue plates industrial product still has a deepdrawn roller and the plates on the 2 products also vary slighty in dimension, making crank  a bit of a pain to fit to automotive product.

I had a big row with a well known engine tuning outfit who were buying iwis chains from OZ for some reason. The chain was industrial but thet swore it was high quality automotive and were marketing it as such. I let them get on with especially as the guy said the people in OZ had stopped trading, which I knew, and he could source the chain anywhere. Surprise that as I sent them samples a couple of years back.

Andy
 

Paul LeClair

Administrator
Staff member
Andychain said:
Cam I had better explain about the duplex. Although I do not own a Laverda, the principles are the same across all machines. In the same way that the simplex G67HP with the big pin is replacing duplex chain in not only motorcycle primary drives on BSA and Maico amonst others, but also in Jag,TVR and Porsche engines, it is simple to deduce that the duplex big pinned Merc chain will replace the triplex.

Over 1 year ago I put several free samples out to Laverda owners and I know some chains were fitted. To date the only  feedback through a thread was that they are very quiet.

If I were racing a Laverda I would adapt the drive to accept 1 of the G67HP chains and change it regularly as the weight saving on reduced sprockets and chain would be good.

It is also nice to hear that the standard rear chain M106SL is working well on a race machine even tho it is in OZ.

Andy 

Hi Andy

I am finally about to fit the chain you sent me last year, thanks again. I will be pulling the primary belt drive off the 79 1200 this week and will run your primary chain for the rest of the summer to compare to the belt. Report will follow in due course.

Paul LeClair
 

Paul LeClair

Administrator
Staff member
Hi Phil

I just removed my primary belt drive and pulleys today and installed Andy Chain's IWIS dupplex primary chain onto triplex sprockets. I took some photos of the process which I will post in due course, but for now a quick "How To" for you to change out your primary chain.

oh, and for those who don't like primary belt drives, this old style white belt has roughly 12,000 kms on it, and the belt and pulleys are still perfect, with the white belt now stained a brownish colour from all that time running in hot oil..... Photos to follow.

So:
1. drain oil, 17 mm wrench to remove drain plug
2. remove any obstruction to primary case removal - in my case, shift lever on the crossover conversion needed to come off. If still left side brake, remove pedal if it obstructs primary case
3. remove the primary chain tensioner, complete - remove cap nut, remove lock nut (both 17 mm wrench) unscrew adjuster with stubby straight screwdriver, which will drain the primary case
4. remove the nine primary case cover bolts (note that the front two are shorter, make sure the short bolts go back in the correct locations)
5. break the primary cover loose DO NOT PRY. I use a rubber mallet, some turn the bike over on the starter motor. The case has to come straight out, what it hangs up on are the two needle bearings in the case, so don't get rough with it
6. from inside the primary cover, remove the tensioner shoe and the mounting pin. Clean up inside the cover, get rid of the dirty oil, check the needle bearings, check the condition of the rubber face on the tensioner.
7. on the crankshaft end, remove the 32 mm nut with a proper snug fitting 32 mm socket. I use an air impact gun so I don't have to dick around with jamming something between the crank gear and the clutch gear to stop the crank turning. This 32 mm nut is normal right hand thread.
8. remove the eight bolts on the clutch housing using a 10 mm socket or wrench. Remove the round metal plate the eight bolts were holding on.
9. wriggle both the front sprocket and rear sprocket off together, with chain still in place. It comes off as a unit.
10. check the condition of the rubber isolator bushes on the clutch drum, replace if necessary.
11. clean up the threads on the crank end with a wire brush or similar.
12. Put the new chain on both front and rear sprockets, offer them up to the clutch drum and crank end as a unit, slide both sprockets into place. On crank end, install the tabbed washer and 32 mm nut, on clutch drum replace thin plate and the eight bolts Tighten to spec.
13. If necessary, install new primary cover gasket. Install tensioner mount pin inside primary cover, install tensioner shoe and spring clip onto pin, offer up entire primary cover, carefully, onto the shaft ends, work into place, once sure square onto shaft ends, tap into place with rubber mallet
14. re-install the primary cover bolts, remember where the two short bolts go. Re-install the tensioner screw - turn in with a short flat balde screwdriver until chain tension is felt, then back off about a half turn, install copper O ring, lock nut, then cap nut.
15.add oil, re-install shift lever or brake lever if removed, test ride, and adjust primary chain tensioner with engine running....

DONE - my time (having done this dozens of times before, using an air impact, and with the bike on a lift table at a convenient working height) - twenty minutes, start to finish. Your time, first time, and blocking crankshaft sprocket to undo the 32 mm nut, give yourself a couple of hours.
MATERIALS REQUIRED
oil, primary cover gasket, primary chain - possibly chain tensioner shoe and possibly clutch drum isolator rubbers
TOOLS REQUIRED
17 mm wrench, 32 mm socket, air impact or means of blocking crankshaft sprocket, 10 mm socket or wrench to remove cluch cover bolts, whatever you need to remove the 9 primary case bolts (mine are stainless steel allan heads), rubber mallet, stubby straight blade screwdriver.

ANDY - the IWIS duplex is a perfect fit for a primary chain, not too tight but so snug there is no slack at all, I fitted to the two inside sprocket teeth, the chain looks really substantial, thanks.

Paul LeClair
 

Paul LeClair

Administrator
Staff member
Hi Bazee

I'll add photos for each step then figure out how to move it to the WIKI, but not for a few days yet. Calgary Stampede is still on here in Calgary until Sunday, busy eating pancakes, drinking beer, watching chuckwagon racing, bull riding, and scantily clad cowgirls........ Yahoooo!

Paul LeClair
 
J

jotapip

Guest
Paul, Many thanks for the clear instructions,i will begin operations at the weekend and let you know how i get on.

Phil.
 

Paul LeClair

Administrator
Staff member
Hi Phil

the instructions I laid out are from my 79 1200, so work on any of the 180 motored bikes except for the very last series, on which the ignition is moved to the primary side and then has to be removed, but then every else remains the same. The instructions will work for your earlier 180.

the only real issue that arises usually is getting the 32 mm nut undone without access to an air impact. Some refer to it as the 'Jesus" nut, as in Jesus this sucker is really on there tight....... and the design is a little odd in that the nut is partly recessed into the crank gear, meaning you can't really get a solid hold on it with a 32 mm wrench and risk wrecking the nut, so it has to be a proper tight fitting 32 mm socket. If you are blocking the gears to prevent the crank from turning, and if you are in the UK, I suspect the ILOC may have the proper Laverda factory sprocket holding tool available for borrowing (?), otherwise a chunk of wood, or even an old brake pad, may work, but be careful about the sprocket teeth and be careful not to damage them.

as a final thought, you will be in deep enough that if you want to check condition of your clutch plates, the clutch drum will slide right off once you have the primary chain off, but can be a bit tricky getting the splines lined back up for re-installation of the clutch drum, especially if your clutch plates still have the anti rattle springs intact.

good luck, using the correct 32 mm socket everything should be straight forward, any questions just post.

Paul LeClair
 
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