March 6th 2014
After the Colston Farm trial (Jiggers Jug) I decided to play with the front suspension and see if that was causing the wandering and bouncing off-line. I was going to get some coil/dampers from Bryan which he had fitted, but then upgraded from. They were pretty new and have progressive rate springs fitted.
When I took mine off and removed the springs I discovered the dampers were actually quite good, so decided to give them another go. I stripped and painted the springs and dampers and also polished the spring platforms, which are alloy. Not that any of this helps the performance, but I like doing it.
I mounted them the right way up this time. Some people say this increases the unsprung weight, which it may do a fraction, but the springs are red now and it looked better this way.
Some also say that oil dampers don't work well upside down. I don't know if they are oil-filled or not.
I also had thought that the rear suspension might be steering the car when it bottomed-out. Which is what it was doing on the Hill I found a problem on.
I'd already raised the spring platform on Ian's side of the car to preload the spring as he has more mass than I do. I raised mine by a similar 1cm and also cranked up the damper adjuster 2 clicks on each side. Ian's side was already 2 clicks up from zero.
So. Ready for the next event, I got bit of bad news in that Ian was working and couldn't get a shift swap for the Sunday meet on 2nd February. I decided to try and find a temporary passenger so that I could still go to the event.
It's at Blaghill which is the site of an old lead mine just North East of Alston, which is the highest market town in England. It's about 1300 ft above sea level up on the Northern Pennines.
It's a steep and hummocky ( I just made that word up) site with no trees. I like sites like that. Not that it makes my performance any better.
I did find a passenger from amongst people I know. A couple of people were keen, but then found they had other commitments. It would be interesting though as Steve, who was up for it, is probably about 11 stone which would make us a balanced crew and would contrast with the usual slightly "tilted" look. Not saying Ian is huge, but he is short and his volume is spread around .....
The weather forecast during the week for Sunday was a fine, sunny day with no wind.
Ha! So much for forecasters.
It was cool and windy with, initially, some fleeting glimpses of our mother star. The cloud started covering over quite soon and the wind started picking up.
We went for a mosey around the site to give Steve a bit of practice at leaning out of the car. After a few climbs (not on the set Hills of course) with about 10psi in the tyres.Then I dropped down to about 4 psi to see if we could get a bit further up the slopes and hope that Steve was getting used to the idea of the angles you get to.
Then the clutch gremlin that I posted about in the last missive struck again. It manifests itself when I try to de-clutch. The pedal is solid and will not shift. The car will usually stall, in gear as it happens when I have been about to slow or stop. It's difficult to select neutral as the car is normally on a steep slope and the weight of the car is preventing deselecting the gear you are in.
Once we got into neutral we free-wheeled down to the pits. I selected the correct tool for dealing with this problem. A hammer.
The recognised method is to tap the clutch release arm where it exits the bellhousing. Upwards seems to work best. This means getting on your back under the car. In the mud. Or worse, sheep shit.
People seemed very jolly at the start and despite the coolness the atmosphere was warm.
We were running just behind Simon. This is a 2-edged sword as you can spot the proper line to use and the technique to follow. On the other hand he makes it look too easy and we usually end up thinking, part-way up the Hill, "why have I stopped here?"
The first two runs before lunch were a bit of a nightmare. We kept getting stopped by the clutch problem. Some people say you don't need to de-clutch on the upward bits, but I like to when manoeuvring. It's just the way I feel comfortable. Watching others you see some do and some don't. The jamming clutch release stops me in my tracks. If I'd been planning to de-clutch and steer, the car just carries on and it's usually too late to use the fiddle brake. If I am planning to use the fiddle for a turn it doesn't really matter as I am not wanting to de-clutch.
Either way, it's not right.
As we moved through the Hills I was jumping out and bashing away with my hammer under the car more and more.
Something needed to be done.
At lunch I spoke with Bryan and a couple of people. We came to the conclusion that the release arm may be over-throwing forwards and getting caught up on the end of the spigot shaft sleeve which the release bearing moves along. I decided that if I adjusted the master cylinder push-rod that attaches to the clutch pedal, I could use the bulkhead as a pedal stop to prevent over-throwing the release arm. The trick was to lower the pedal enough to prevent problems but retain enough movement to release the clutch.
It sort of worked. The clutch did still slightly jam but stamping on the pedal cleared it.
This brought about a great increase in our performance and we did a lot better. However as it was so cold, with sleet and rain in the wind, the organisers sensibly decided to do just one run after lunch. The marshals at the top of the site must have been freezing.
Another thing we tried was on the climb between Hills 1 and 2 and the remaining four Hills at the top of the site. It was pretty steep and bumpy. I had to take a few runs at it to get up initially. The car was losing grip as the bumps upset it.
So after getting stopped partway up we backed down and I slackened off the setting on the rear dampers by a couple of clicks. The next attempt we ran straight up with no problem.
As a novice facts like this are difficult to find. Ask people and some are unsure or hazy (or keeping quiet!) about things like this. But here I had back-to-back attempts which showed better result from a softer back end.
However this is great for our new, svelte, lightweight crew, but when we are running with Ian as passenger the tendency to bottom-out is still there. I did put 125 lb/inch springs on (previously 100lb/inch) but without some compression stiffness wound into the damper, they still bottom on the bump rubbers.
Bryan has lent me some progressive springs to try. They are 120/160 lb/inch so may be what's needed to control the back end.
The better control of the suspension really helped on a couple of oblique passes over steep banks which some cars seemed to lurch over and we seemed to just pass over quite smoothly. In the past I would have expected to head off in the wrong direction in that situation. (See Simon at 44 seconds in the video. Our car managed that in a similar way).
Still not World-Beating but these little things give you the confidence to expect to go in the direction you intend.
I managed to snatch this video from my temporary passenger, Steve, who filmed it on his iPhone. The second car is driven by Simon who won the event. The other car is Jeff who came 9th. We came 19th. Not last. I've left the wind noise in as it helps to give a feeling of how chilly it was.
When I took mine off and removed the springs I discovered the dampers were actually quite good, so decided to give them another go. I stripped and painted the springs and dampers and also polished the spring platforms, which are alloy. Not that any of this helps the performance, but I like doing it.
I mounted them the right way up this time. Some people say this increases the unsprung weight, which it may do a fraction, but the springs are red now and it looked better this way.
Some also say that oil dampers don't work well upside down. I don't know if they are oil-filled or not.
I also had thought that the rear suspension might be steering the car when it bottomed-out. Which is what it was doing on the Hill I found a problem on.
I'd already raised the spring platform on Ian's side of the car to preload the spring as he has more mass than I do. I raised mine by a similar 1cm and also cranked up the damper adjuster 2 clicks on each side. Ian's side was already 2 clicks up from zero.
So. Ready for the next event, I got bit of bad news in that Ian was working and couldn't get a shift swap for the Sunday meet on 2nd February. I decided to try and find a temporary passenger so that I could still go to the event.
It's at Blaghill which is the site of an old lead mine just North East of Alston, which is the highest market town in England. It's about 1300 ft above sea level up on the Northern Pennines.
It's a steep and hummocky ( I just made that word up) site with no trees. I like sites like that. Not that it makes my performance any better.
I did find a passenger from amongst people I know. A couple of people were keen, but then found they had other commitments. It would be interesting though as Steve, who was up for it, is probably about 11 stone which would make us a balanced crew and would contrast with the usual slightly "tilted" look. Not saying Ian is huge, but he is short and his volume is spread around .....
The weather forecast during the week for Sunday was a fine, sunny day with no wind.
Ha! So much for forecasters.
It was cool and windy with, initially, some fleeting glimpses of our mother star. The cloud started covering over quite soon and the wind started picking up.
We went for a mosey around the site to give Steve a bit of practice at leaning out of the car. After a few climbs (not on the set Hills of course) with about 10psi in the tyres.Then I dropped down to about 4 psi to see if we could get a bit further up the slopes and hope that Steve was getting used to the idea of the angles you get to.
Then the clutch gremlin that I posted about in the last missive struck again. It manifests itself when I try to de-clutch. The pedal is solid and will not shift. The car will usually stall, in gear as it happens when I have been about to slow or stop. It's difficult to select neutral as the car is normally on a steep slope and the weight of the car is preventing deselecting the gear you are in.
Once we got into neutral we free-wheeled down to the pits. I selected the correct tool for dealing with this problem. A hammer.
The recognised method is to tap the clutch release arm where it exits the bellhousing. Upwards seems to work best. This means getting on your back under the car. In the mud. Or worse, sheep shit.
People seemed very jolly at the start and despite the coolness the atmosphere was warm.
We were running just behind Simon. This is a 2-edged sword as you can spot the proper line to use and the technique to follow. On the other hand he makes it look too easy and we usually end up thinking, part-way up the Hill, "why have I stopped here?"
The first two runs before lunch were a bit of a nightmare. We kept getting stopped by the clutch problem. Some people say you don't need to de-clutch on the upward bits, but I like to when manoeuvring. It's just the way I feel comfortable. Watching others you see some do and some don't. The jamming clutch release stops me in my tracks. If I'd been planning to de-clutch and steer, the car just carries on and it's usually too late to use the fiddle brake. If I am planning to use the fiddle for a turn it doesn't really matter as I am not wanting to de-clutch.
Either way, it's not right.
As we moved through the Hills I was jumping out and bashing away with my hammer under the car more and more.
Something needed to be done.
At lunch I spoke with Bryan and a couple of people. We came to the conclusion that the release arm may be over-throwing forwards and getting caught up on the end of the spigot shaft sleeve which the release bearing moves along. I decided that if I adjusted the master cylinder push-rod that attaches to the clutch pedal, I could use the bulkhead as a pedal stop to prevent over-throwing the release arm. The trick was to lower the pedal enough to prevent problems but retain enough movement to release the clutch.
It sort of worked. The clutch did still slightly jam but stamping on the pedal cleared it.
This brought about a great increase in our performance and we did a lot better. However as it was so cold, with sleet and rain in the wind, the organisers sensibly decided to do just one run after lunch. The marshals at the top of the site must have been freezing.
Another thing we tried was on the climb between Hills 1 and 2 and the remaining four Hills at the top of the site. It was pretty steep and bumpy. I had to take a few runs at it to get up initially. The car was losing grip as the bumps upset it.
So after getting stopped partway up we backed down and I slackened off the setting on the rear dampers by a couple of clicks. The next attempt we ran straight up with no problem.
As a novice facts like this are difficult to find. Ask people and some are unsure or hazy (or keeping quiet!) about things like this. But here I had back-to-back attempts which showed better result from a softer back end.
However this is great for our new, svelte, lightweight crew, but when we are running with Ian as passenger the tendency to bottom-out is still there. I did put 125 lb/inch springs on (previously 100lb/inch) but without some compression stiffness wound into the damper, they still bottom on the bump rubbers.
Bryan has lent me some progressive springs to try. They are 120/160 lb/inch so may be what's needed to control the back end.
The better control of the suspension really helped on a couple of oblique passes over steep banks which some cars seemed to lurch over and we seemed to just pass over quite smoothly. In the past I would have expected to head off in the wrong direction in that situation. (See Simon at 44 seconds in the video. Our car managed that in a similar way).
Still not World-Beating but these little things give you the confidence to expect to go in the direction you intend.
I managed to snatch this video from my temporary passenger, Steve, who filmed it on his iPhone. The second car is driven by Simon who won the event. The other car is Jeff who came 9th. We came 19th. Not last. I've left the wind noise in as it helps to give a feeling of how chilly it was.
The others are here on Youtube.
The next post will be about the resolution of the clutch problem. Honest
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