Now this is the first ever motorcycle that I have had that has:- 1) Monoshock rear suspension 2) Rear suspension that has totally adjustable preload and that has adjustable damping/rebound? Now I am seeing and reading on youtube and forums that one is supposed to set up the bike for your weight so that it handles properly most had before was the ramped spring collar found on the rear shocks! Also read that Ducati sort of sets up their bikes new for a 73kg (160 lb) rider and I weigh a mite bit more than that at 105kg (230 lbs) so according to what have seen the rear needs to be wound up a little ....... probably need to get the nephew to help me measure how much sag we have when I put my bum on the seat. As far as I am aware the suspension is still at standard settings. What is you take on just how important it is to set up the bike? Plezier
Hello. Great choice! Ideally set up for your weight, ie set static sag then set rider sag: this will tell you if you need heavier spring. The monster tends to be a little soft at the rear ime anyway where most Ducatis are set up for a 25st rider rear and 10st rider front suspension If you do want to change the spring, it’s easy enough to do, especially if you have access to two pairs of hands.
Thanks but Iwould have to let a shop change the spring as do not have a sturdy work bench and do not have a vice now. Something that I must address at some point. As for sag will have to rope the nephew into measuring it when I sit on the bike and to get the 30% that they say is about ideal we need it to be 103.6mm for the ear and 91mm for the front. Have just partly watched a Dave Moss vid on setting up a bike for yourself and damn it seems that I was 45 years ahead of the times when I got my 79 Bonnieville as I changed things to suit me. After a while noticed a pain in the top of my left shoulder and concluded that the bars did not suit me so changed them to give my hands a more natural position. Turned out that a set of bars off a Yamaha RD250 suited me well of course had to change brake hose as original was too short but a trip around the corner to Berite Motor Factors soon sorted that out. My motorcylce boots had steel toecaps under the leather and the gear lever was too long for my smaller foot (size 8) and missed the change pad on the boot and hit the steel cap and started to wear through the leather. So I cut an inch or so out of the middle on the lever had the welder at work weld it back together then dressed it down all smooth and got our neighbour to take it into work and rechrome it. Lucky for me this was free and a really good job was done they even repolished it suggesting that my efforts were not good enough ............. reason for it being free was that they owned the plating firm and it was big enough to have contracts with Ford for chroming. So basically I fitted the bike to myself! Have popped the tank and seat back on the Monster and just sat on it the leg position is right my feet positions are correct however the bars are wrong they are too wide and straight what I need is some that are or can be cut down to about 28" length and that have the portion that holds the levers and grips angle downand back a little to make it a natual positon for me. Time to search the web. Plezier
Are you sure those figures are correct? They imply a total wheel/suspension travel of 311.8mm for the rear, and 273mm for the front That’s off-road/MX/Enduro levels of wheel travel. The quoted travel is 130mm front, 148mm rear so you should be aiming for 39mm front and 44-45mm rear. Those figures being the total sag with you sat on the bike ie static sag + rider sag. Your figures are 70% of the total possible travel.
LOL ahh yes I simply took 30% away from the total travel but not applied to the bikes height as yet. Plezier
As far as I am aware there is no adjustmet in the front on the 2002 620ie Dark only the Sachs shock in the rear is adjustable sadly the smaller Monsters are very neglected on the web! You can find service vids and tutorials for normal servicing for the engine and how to remove the tank and for US model how to delete the emmission cannister but that about it have not been able to find a single one or article on adjusting the 600 or 620's suspension it's alsmost as if they are too small to be worth the bother it all seems to start at 800cc and up even the poor ole 750 is largely ignored. Plezier
Optimum setting for total sag for the road is always 30-33% of total suspension travel afaik. However, the feel of the suspension is a very subjective matter so it’s always a case of tweak and ride and whatever works best for the owner.
iirc you are correct the standard front suspension on the 620 was non-adjustable. However, there’s nothing to stop you picking up a set of fully adjustable forks off one of its bigger brothers from the same year, servicing them, and they should just swap straight in.
Thank you for that have been watching some Dave Moss videos but not found or seen that one before of course that is no longer true as just watched it. Now we know for sure that my bike had been dropped the gear lever shows this and yesterday discovered that the clutch lever had been welded back together at some point in time. Looking closed found the the allo headlight bracket was slightly bent so straightened that up and the handlebars have been changed at some point the is a bar dent in the left side of the tank so bars were bent enough to contact the tank an probably explains why the aftermarkt bars on it. Am looing to change those anyway to a narrower set as they are a bit too wide for me to be confortable plus I don;t really like the off road cross brace that an add on with them. With only just over 7,600 mile on it I doubt the rear shock has been pounded and as yet have not touched it except to clean muck off it same with the front forks though on age along the fork oil could most likely do with a change not sure if it can be on the Sachs rear unit. My forks seem to work smoothly but it's something that I nee to look at. On another note the bike is now insured as it has not registration it's on the chassis/frame number and once we have a reg number they change it on the policy document which hopefull we will have in a coule of days, Plezier
This is for a 900ss, but you can still use the figures as a guide. OEM Showa Suspension Setup I. Set Preload (a/k/a ride height or sag) before adjusting compression and rebound damping (900SS Showa's: 14 revolutions preload adjustment on forks and ring preload adjustment on rear shock). A. Static/Free Sag: 1. Lift motorbike off the ground, including F and R wheels, so that the suspension is topped out (i.e.: the bike's weight is not compressing the suspension at all; cannot use stands to do this). 2. With motorbike/wheels lifted, for F wheel, measure distance of suspension travel with zip-tie on fork leg; and for R wheel, measure distance from a point on bike to rear axle that is perpendicular to ground. 3. Repeat measurements but now with bike on ground loading suspension. 4. Difference between suspension topped out and bike on ground and loading suspension is free sag: a. Front suspension: 20 -- 30mm free sag. b. Rear suspension: 5 -- 10mm free sag. 5. If free sag is not within above range, may need to change spring rates. B. Rider Sag: 1. Repeat free sag measurements above but this time with rider/gear on bike and with rider (and weight distribution) in normal riding position. 2. Difference between suspension topped out and with rider/gear on bike and loading suspension is static/rider sag (should use about 1/3 of the total suspension available): a. Front suspension: for 120mm of total travel, there should be approximately 30mm (race) -- 40mm (street) rider sag. b. Rear suspension: for 65mm of total travel, there should be approximately 15mm (race) -- 21mm (street) rider sag. C. Adjust preload so that static/rider sag is within proper range. 1. Not enough (symptoms): spring not properly loaded; inefficient. 2. Too much (symptoms): harsh ride; poor traction. II. Adjust forks (900SS Showa: 14 click adjustment for compression and rebound). A. Set preload properly (see above). B. Front rebound damping is located at top of fork; spec is 4 clicks out (counterclockwise) from max (fully screwed in clockwise). 1. Not enough (symptoms): pogo effect during transitions; bike rises too much when flicked; loose and imprecise bike/front; understeers & bike/front turns wide (solution: 2 clicks in). 2. Too much (symptoms): suspension is packing down; bike/front chatters over ripples; front doesn’t ride down backside of bump; harsh ride over bumps; oversteers & bike/front wants to tuck-in in corners; poor front tire grip; tank slap under acceleration (solution: 2 clicks out). C. Front compression damping is located at bottom of fork; spec is 6 clicks out (counterclockwise) from max (fully screwed in clockwise). 1. Not enough (symptoms): fork bottoms out; front dives excessively during braking; front feels vague; bike wallows in transitions (solution: 2 clicks in). 2. Too much (symptoms): chatter at handlebars even when not braking; fork jumps off crest of bump instead of riding down it; harsh ride over bumps; front rides high in corners; understeers & bike/front turns wide (solution: 2 clicks out). III. Adjust shock (900SS Showa: screw adjustment for compression and rebound). A. Set preload properly (see above). B. Rear rebound damping is located at bottom of shock; spec is 1 full turn out (counterclockwise) from max (fully screwed in clockwise). 1. Not enough (symptoms): pogo effect during transitions; bike rises too much when flicked; loose and imprecise bike/rear; bike wallows/weaves over bumps; decreased traction (solution: screw in 2 turns). 2. Too much (symptoms): suspension is packing down; bike/rear chatters over ripples; harsh ride over bumps; slow steering; understeers & bike turns wide (solution: screw out 2 turns). C. Rear compression damping is located at top of shock; spec is 1 full turn out (counterclockwise) from max (fully screwed in clockwise). 1. Not enough (symptoms): shock bottoms out; too much rear squat during acceleration causing front to lose grip/lighten; rear bumps sideways during acceleration out of corners; bike wallows in transitions; understeers & bike turns wide (solution: screw in 2 turns). 2. Too much (symptoms): lack of rear squat during acceleration; harsh ride over bumps, which increases with speed; rear kicks out/skips over medium/large bumps (solution: screw out 2 turns). IV. To quicken steering, move front forks up in the triple claims and/or increase the rear shock's length (if available). V. Remember to record all adjustments and to make changes to suspension (rebound and compression as well as forks and shock) one at a time.
Thank you I will go through the rear with the help of my nephew front forks though except for changing the oil there is nothing else to do with them as thereare no adjusters at all on them. Plezier
Ahhhh where is here? Remember that I am in SE Europe...Bulgaria. Plus do I need a set of adjustable forks? never had them before on any of my bikes. Oh sorry tell a lie an Aeriel with rigid frame (1947) that I was restoring back in 83/4 had aira djustable Dowety telescopic forks. Never got finsihed as some scumbag broke into the lock up that a couple of friends and I had bikes in and stole the lot, bikes, tools everything. Plezier
Well finally took a look at that rear shock and it's not a happy tale as someone had brutalised the castle nuts. I had to use the same method to try and unlock the top nut and did eventually get it to move slightly but it was taking the bottom nut wiht it. Then I tried a scissor type oil filter wrench and managed to unscrew them slightly and eventually they did seperate. Had to use penetrating fluid on the shock body threads and scrub with a toothbrush then when they were seperated got a file and filed off all the burrs that I could. The tension on the spring was quite wound up as when you lifted the bike upright off it's side stand it did not sag at all and if you tried to lift the back of the bike there was no movement is was already right at the top. So had to back off the pressure so we now do have a bit of movement when the rear is lifted and sag with me sat on it is between 25-30mm. Another oddity is that I cleaned the screw first again the screwed in the damping adjuster to see where we are set at and it took 16 clicks to reach fully in I then unscewed it and got quite worried as it went past the 22 clicks that everyoone says this shock has and it just kept going it finally stopped at 35 clicks have wound it back in and counted again and yep this shock has 35 clicks of adjustment . So have set it to 17 clicks which is about where it was before and we will see how it feels when we can eventually ride it on the road, The front forks had a lot of sticktion so lifted the fork seal with a small screw driver and shot a bit of aerosol grease under them the dust seal really could do with renewing however there is click or slight knock on the front that have not been able to track down. First thought was head stock bearing dry/rusted but you can usually feel that in turning the forks left-right and rocking the bike on the front brake there is not knock felt on the top yoke (Triple clamp) going to have to ask ML Racing to have a looksee if I can get it booked in with them after we get it re-registered. Plezier
If you have your Rider SAG right at about 30%, you can start tweaking the comp and rebound. Wrap a cable tie around your front fork as a measuring tool. You should be using 3/4 of the fork travel measured to the bottom-out mark above the fork casting and that's while riding on smooth roads without pushing it. If riding more aggressively or on rougher roads, the zip-tie can drop another half inch. In an emergency stop, the zip-tie can drops to just above the bottom-out mark without bottoming-out. Adjust the comp damping accordingly. It's also important that some of these settings should be reviewed every 3000 miles or so as the oil's viscosity deteriorates. Consequently, I consider suspension set-up as a journey, not a destination. I keep tweaking the compression and rebound settings to see what's best given a particular riding scenario. Keeping a record of these settings is an essential step in this journey. BTW, Has the suspension ever been serviced? If not you may want to consider a fork kit and shock upgrade.
Thank you for you comments and to answer your question no not as far as I know the suspension has never been serviced in fact the plugs in the top of the fork legs seem to be siezed in place and I have been unable to undo them so am hoping the get the bike into the local independant shop and let them service the forks which are non adjustable. The Mono shock it's claimed to be non serviciable but it is adjustable. As for the cable tie I put one on the right fork leg just after getting the bike and also lifted the dust seals and applied a little spray grease under them to free up the "Stiction" that they suffered from. They do seem to dive rather easily under braking This is after a normal ride out no heavy braking but the access tack to home is no way smooth it's unmade loose stone so the suspension has to work more of course maybe I should slide the tie back up and take a photo after a ride on the normal tarmac road down to the village that's 5 miles or so. As for the SAG well when I got the bike there did not appear to be any on the rear so had to "soften" the rear shock setting and have no idea as to when or if it had been played with before and I still really have no idea if the shock is set up properly or not and if it has the origianl factory spring on it or not there is no service history with it. Now bearing in mind that the bike is 22 years old even if it has fairly few miles on it with 8994 on the clock it had 7677 on it when I got it so I have done 1317 miles on it. Another thing that I find odd is that I cannot recall there being an fork oil change interval mentioned for my 79 Bonnieville likewise there was no service shedule for the rear shocks those were Girling Gas shocks odd how they have got back to oil now. Plezier
Fork travel look alright. IDK about the front SAG but based on travel It may not be too far off the mark. Compression damping can mask an incorrect SAG but since you have fork dive, I can't blame compression damping for being to high. Oil viscosity may be non-existent given the age.
